The Birth of Venus

For other uses, see The Birth of Venus (disambiguation).

Sandro Botticelli, The Birth of Venus (c. 1484-86). Tempera on canvas. 172.5 cm × 278.9 cm (67.9 in × 109.6 in). Uffizi, Florence

Detail: the face of Venus

The Birth of Venus (Italian: Nascita di Venere [ˈnaʃʃita di ˈvɛːnere]) is a painting by the Italian artist Sandro Botticelli probably made in the mid 1480s. It depicts the goddess Venus arriving at the shore after her birth, when she had emerged from the sea fully-grown (called Venus Anadyomene and often depicted in art). The painting is in the Uffizi Gallery in Florence, Italy.

Although the two are not a pair, the painting is inevitably discussed with Botticelli’s other very large mythological painting, the Primavera, also in the Uffizi. They are among the most famous paintings in the world, and icons of the Italian Renaissance; of the two, the Birth is even better known than the Primavera.[1] As depictions of subjects from classical mythology on a very large scale they were virtually unprecedented in Western art since classical antiquity, as was the size and prominence of a nude female figure in the Birth. It used to be thought that they were both commissioned by the same member of the Medici family, but this is now uncertain.

They have been endlessly analysed by art historians, with the main themes being: the emulation of ancient painters and the context of wedding celebrations (generally agreed), the influence of Renaissance Neo-Platonism (somewhat controversial), and the identity of the commissioners (not agreed). Most art historians agree, however, that the Birth does not require complex analysis to decode its meaning, in the way that the Primavera probably does. While there are subtleties in the painting, its main meaning is a straightforward, if individual, treatment of a traditional scene from Greek mythology, and its appeal is sensory and very accessible, hence its enormous popularity.[2]

Contents

  • 1 Description and subject
  • 2 Technical
  • 3 Style
  • 4 Dating and history
  • 5 Interpretations
    • 5.1 Literary sources
    • 5.2 Ancient art
    • 5.3 Mack
  • 6 Derivative versions
  • 7 Notes
  • 8 References
  • 9 External links

Description and subject[edit]

The Hora of Spring

In the centre the newly-born goddess Venus stands nude in a giant scallop shell. Its size is purely imaginary, and is also found in classical depictions of the subject.[3] At the left the wind god Zephyr blows at her, with the wind shown by lines radiating from his mouth. He is in the air, and carries a young female, who is also blowing, but less forcefully. Both have wings. Vasari was probably correct in identifying her as “Aura”, personification of a lighter breeze.[4] Their joint efforts are blowing Venus towards the shore, and blowing the hair and clothes of the other figures to the right.[5]

At the right a female figure who may be floating slightly above the ground holds out a rich cloak or dress to cover Venus when she reaches the shore, as she is about to do. She is one of the three Horae or Hours, Greek minor goddesses of the seasons and of other divisions of time, and attendants of Venus. The floral decoration of her dress suggests she is the Hora of Spring.[6]

Alternative identifications for the two secondary female figures involve those also found in the Primavera; the nymph held by Zephyr may be Chloris, a flower nymph he married in some versions of her story, and the figure on land may be Flora.[7] Flora is generally the Roman equivalent of the Greek Chloris; in the Primavera Chloris is transformed into the figure of Flora next to her, following Ovid’s Fasti,[8] but it is hard to see that such a transformation is envisaged here. However, the roses blown along with the two flying figures would be appropriate for Chloris.

The subject is not strictly the “Birth of Venus”, a title only given the painting in the nineteenth century (though given as the subject by Vasari), but the next scene in her story, where she arrives on land, blown by the wind. The land probably represents either Cythera or Cyprus, both Mediterranean islands regarded by the Greeks as territories of Venus.[9]

Technical[edit]

The painting is large, but slightly smaller than the Primavera, and where that is a panel painting, this is on the cheaper support of canvas. Canvas was increasing in popularity, perhaps especially for secular paintings for country villas, which were decorated more simply, cheaply and cheerfully than those for city palazzi, being designed for pleasure more than ostentatious entertainment.[10]

The painting is on two pieces of canvas, sewn together before starting, with a gesso ground tinted blue. There are differences to Botticelli’s usual technique, working on panel supports, such as the lack of a green first layer under the flesh areas. There are a number of pentimenti revealed by modern scientific testing. The Hora originally had “low classical sandals”, and the collar on the mantle she holds out is an afterthought. The hair of Venus and the flying couple was changed. There is heavy use of gold as a pigment for highlights, on hair, wings, textiles, the shell and the landscape. This was all apparently applied after the painting was framed. It was finished with a “cool gray varnish”, probably using egg yolk.[11]

As in the Primavera, the green pigment used for the wings of Zephyr and his companion and the leaves of the orange trees on the land has darkened considerably with exposure to light over time, somewhat distorting the intended balance of colours. Parts of some leaves at the top right corner, normally covered by the frame, have been less affected.[12] The blues of the sea and sky have also lost their brightness.[13]

Style[edit]

Venus

Although the pose of Venus is classical in some respects, and borrows the position of the hands from the Venus Pudica type in Greco-Roman sculptures (see section below), the overall treatment of the figure, standing off-centre with a curved body of long flowing lines, is in many respects from Gothic art. Kenneth Clark wrote: “Her differences from antique form are not physiological, but rhythmic and structural. Her whole body follows the curve of a Gothic ivory. It is entirely without that quality so much prized in classical art, known as aplomb; that is to say, the weight of the body is not distributed evenly either side of a central plumb line. …. She is not standing but floating. … Her shoulders, for example, instead of forming a sort of architrave to her torso, as in the antique nude, run down into her arms in the same unbroken stream of movement as her floating hair.”[14]

Venus’ body is anatomically improbable, with elongated neck and torso. Her pose is impossible: although she stands in a classical contrapposto stance, her weight is shifted too far over the left leg for the pose to be held. The proportions and poses of the winds to the left do not quite make sense, and none of the figures cast shadows.[15] The painting depicts the world of the imagination rather than being very concerned with realistic depiction.[16]

Ignoring the size and positioning of the wings and limbs of the flying pair on the left, which bother some other critics, Kenneth Clark calls them:

…perhaps the most beautiful example of ecstatic movement in the whole of painting. … the suspension of our reason is achieved by the intricate rhythms of the drapery which sweep and flow irresistibly around the nude figures. Their bodies, by an endless intricacy of embrace, sustain the current of movement, which finally flickers down their legs and is dispersed like an electric charge.[17]

Botticelli’s art was never fully committed to naturalism; in comparison to his contemporary Domenico Ghirlandaio, Botticelli seldom gave weight and volume to his figures and rarely used a deep perspectival space.[15] Botticelli never painted landscape backgrounds with great detail or realism, but this is especially the case here. The laurel trees and the grass below them are green with gold highlights, most of the waves regular patterns, and the landscape seems out of scale with the figures.[18] The clumps of bulrushes in the left foreground are out of place here, as they come from a freshwater species.[19]

Dating and history[edit]

It has long been suggested that Botticelli was commissioned to paint the work by the Medici family of Florence, perhaps by Lorenzo di Pierfrancesco de’ Medici (1463–1503) a major patron of Botticelli, under the influence of his cousin Lorenzo de’ Medici, “il Magnifico”. This was first suggested by Herbert Horne in his monograph of 1908, the first major modern work on Botticelli, and long followed by most writers, but more recently has been widely doubted, though it is still accepted by some. Various interpretations of the painting rely on this origin for its meaning. Although relations were perhaps always rather tense between the Magnifico and his young cousins and wards, Lorenzo di Pierfrancesco and his brother Giovanni di Pierfrancesco de’ Medici, it may have been politic to commission a work that glorified the older Lorenzo, as some interpretations have it. There may be a deliberate ambiguity as to which Lorenzo was intended to be evoked. In later years hostility between the two branches of the family became overt.

Horne believed that the painting was commissioned soon after the purchase in 1477 of the Villa di Castello, a country house outside Florence, by Lorenzo and Giovanni, to decorate their new house, which they were rebuilding. This was the year after their father died at the age of 46, leaving the young boys wards of their cousin Lorenzo il Magnifico, of the senior branch of the Medici family and de facto ruler of Florence.[20] There is no record of the original commission, and the painting is first mentioned by Vasari, who saw it, together with the Primavera, at Castello, some time before the first edition of his Lives in 1550, probably by 1530–40. In 1550 Vasari was himself painting in the villa, but he very possibly visited it before that. But in 1975 it emerged that, unlike the Primavera, the Birth is not in the inventory, apparently complete, made in 1499 of the works of art belonging to Lorenzo di Pierfrancesco’s branch of the family. Ronald Lightbown concludes that it only came to be owned by the Medici after that. The inventory was only published in 1975, and made many previous assumptions invalid.[21]

Horne dated the work at some point after the purchase of the villa in 1477 and before Botticelli’s departure for Rome to join the painting of the Sistine Chapel in 1481. Recent scholars prefer a date of around 1484–86 on grounds of the work’s place in the development of Botticelli’s style. The Primavera is now usually dated earlier, after Botticelli’s return from Rome in 1482 and perhaps around the time of Lorenzo di Pierfrancesco’s wedding in July 1482,[22] but by some still before Botticelli’s departure.[23]

Whenever the two paintings were united at Castello, they have remained together ever since. They stayed in Castello until 1815, when they were transferred to the Uffizi. For some years until 1919 they were kept in the Galleria dell’Accademia, another government museum in Florence.[24]

Interpretations[edit]

Although there are ancient and modern texts that are relevant, no single text provides the precise imagery of the painting, which has led scholars to propose many sources and interpretations.[25] Many art historians who specialize in the Italian Renaissance have found Neoplatonic interpretations, of which two different versions have been articulated by Edgar Wind and Ernst Gombrich,[26] to be the key to understanding the painting. Botticelli represented the Neoplatonic idea of divine love in the form of a nude Venus.[27]

For Plato – and so for the members of the Florentine Platonic Academy – Venus had two aspects: she was an earthly goddess who aroused humans to physical love or she was a heavenly goddess who inspired intellectual love in them. Plato further argued that contemplation of physical beauty allowed the mind to better understand spiritual beauty. So, looking at Venus, the most beautiful of goddesses, might at first raise a physical response in viewers which then lifted their minds towards the godly.[28] A Neoplatonic reading of Botticelli’s Birth of Venus suggests that 15th-century viewers would have looked at the painting and felt their minds lifted to the realm of divine love.

The composition, with a central nude figure, and one to the side with an arm raised above the head of the first, and winged beings in attendance, would have reminded its Renaissance viewers of the traditional iconography of the Baptism of Christ, marking the start of his ministry on earth. In a similar way, the scene shows here marks the start of Venus’s ministry of love, whether in a simple sense, or the expanded meaning of Renaissance Neoplatonism.[29]

More recently, questions have arisen about Neoplatonism as the dominant intellectual system of late 15th-century Florence,[30] and scholars have indicated that there might be other ways to interpret Botticelli’s mythological paintings. In particular, both Primavera and Birth of Venus have been seen as wedding paintings that suggest appropriate behaviors for brides and grooms.[31]

The laurel trees at right and laurel wreath worn by the Hora are punning references to the name “Lorenzo”, though it is uncertain whether Lorenzo il Magnifico, the effective ruler of Florence, or his young cousin Lorenzo di Pierfrancesco is meant. In the same way the flowers in the air around Zephyr and on the textiles worn and carried by the Hora evoke the name of Florence.[32]

Literary sources[edit]

Roman fresco from the “House of Venus” in Pompeii, 1st century BC

The closest precedent for the scene is generally agreed to be in one of the early ancient Greek Homeric Hymns, published in Florence in 1488 by the Greek refugee Demetrios Chalkokondyles:

Of august gold-wreathed and beautiful
Aphrodite I shall sing to whose domain
belong the battlements of all sea-loved
Cyprus where, blown by the moist breath
of Zephyros, she was carried over the
waves of the resounding sea on soft foam.
The gold-filleted Horae happily welcomed
her and clothed her with heavenly raiment.[33]

This poem was probably already known to Botticelli’s Florentine contemporary, and Lorenzo di Medici’s court poet, Angelo Poliziano. The iconography of The Birth of Venus is similar to a description of a relief of the event in Poliziano’s poem the Stanze per la giostra, commemorating a Medici joust in 1475, which may also have influenced Botticelli, although there are many differences. For example Poliziano talks of multiple Horae and zephyrs.[34] Older writers, following Horne, posited that “his patron Lorenzo di Pierfrancesco asked him to paint a subject illustrating the lines”,[35] and that remains a possibility, though one difficult to maintain so confidently today. Another poem by Politian speaks of Zephyr causing flowers to bloom, and spreading their scent over the land, which probably explains the roses he blows along with him in the painting.[36]

Ancient art[edit]

Capitoline Venus, derived from Aphrodite of Cnidus

Venus de’ Medici

Having a large standing female nude as the central focus was unprecedented in post-classical Western painting, and certainly drew on the classical sculptures which were coming to light in this period, especially in Rome, where Botticelli had spent 1481–82 working on the walls of the Sistine Chapel.[37] The pose of Botticelli’s Venus follows the Venus Pudica (“Venus of Modesty”) type from classical antiquity, where the hands are held to cover the breasts and groin; in classical art this is not associated with the new-born Venus Anadyomene. What became a famous example of this type is the Venus de’ Medici, a marble sculpture that was in a Medici collection in Rome by 1559, which Botticelli may have had opportunity to study (the date it was found is unclear).[38]

The painter and the humanist scholars who probably advised him would have recalled that Pliny the Elder had mentioned a lost masterpiece of the celebrated ancient Greek painter, Apelles, representing Venus Anadyomene (Venus Rising from the Sea). According to Pliny, Alexander the Great offered his mistress, Pankaspe, as the model for the nude Venus and later, realizing that Apelles had fallen in love with the girl, gave her to the artist in a gesture of extreme magnanimity. Pliny went on to note that Apelles’ painting of Pankaspe as Venus was later “dedicated by Augustus in the shrine of his father Caesar.” Pliny also stated that “the lower part of the painting was damaged, and it was impossible to find anyone who could restore it. . . . This picture decayed from age and rottenness, and Nero… substituted for it another painting by the hand of Dorotheus”.

Pliny also noted a second painting by Apelles of Venus “superior even to his earlier one,” that had been begun by artist but left unfinished. The Roman images in various media showing the new-born Venus in a giant shell may well be crude derivative versions of these paintings. Botticelli could not have seen the frescos unearthed later in Pompeii, but may well have seen small versions of the motif in terracotta or engraved gems. The “House of Venus” in Pompeii has a life-size fresco of Venus lying in the shell, also seen in other works; in most other images she stands with her hands on her hair, wringing the water from it, with or without a shell.

The two-dimensionality of this painting may be a deliberate attempt to evoke the style of ancient Greek vase painting or frescos on the walls of Etruscan tombs,[39] the only types of ancient painting known to Botticelli.

  • Greco-Roman Venus Anadyomene

  • Greco-Roman bronze statuette

  • Roman glass cameo Venus Anadyomene

  • Greek terracotta, from Pontus

Mack[edit]

Zephyr and his companion

Another interpretation of the Birth of Venus is provided here by its author, Charles R. Mack. This interpretation takes much that is generally agreed, but Mack goes on to explain the painting as an allegory extolling the virtues of Lorenzo de’ Medici.[40] This has not been adopted by Renaissance art historians in general,[41] and it remains problematic, since it depends on the painting being commissioned by the Medici, yet the work is not documented in Medici hands until well into the following century.

Mack sees the scene as inspired by both the Homeric Hymn and the ancient paintings. But something more than a rediscovered Homeric hymn was likely in the mind of the Medici family member who commissioned this painting from Botticelli. Once again, Botticelli, in his version of the Birth of Venus, might be seen as completing the task begun by his ancient predecessor Apelles, even surpassing him. Giving added support to this interpretation of Botticelli as a born-again Apelles is the fact that that very claim was voiced in 1488 by Ugolino Verino in a poem entitled “On Giving Praise to the History of Florence.”[42]

While Botticelli might well have been celebrated as a revivified Apelles, his Birth of Venus also testified to the special nature of Florence’s chief citizen, Lorenzo de’ Medici. Although it now seems that the painting was executed for another member of the Medici family, it likely was intended to celebrate and flatter its head, Lorenzo de’ Medici. Tradition associates the image of Venus in Botticelli’s painting with the famous beauty Simonetta Cattaneo Vespucci, of whom popular legend claims both Lorenzo and his younger brother, Giuliano, were great admirers. Simonetta was possibly born in the Ligurian seaside town of Portovenere (‘the port of Venus’). Thus, in Botticelli’s interpretation, Pankaspe (the ancient living prototype of Simonetta), the mistress of Alexander the Great (the Laurentian predecessor), becomes the lovely model for the lost Venus executed by the famous Greek painter Apelles (reborn through the recreative talents of Botticelli), which ended up in Rome, installed by Emperor Augustus in the temple dedicated to Florence’s supposed founder Julius Caesar.

In the case of Botticelli’s Birth of Venus, the suggested references to Lorenzo, supported by other internal indicators such as the stand of laurel bushes at the right, would have been just the sort of thing erudite Florentine humanists would have appreciated. Accordingly, by overt implication, Lorenzo becomes the new Alexander the Great with an implied link to both Augustus, the first Roman emperor, and even to Florence’s legendary founder, Caesar himself. Lorenzo, furthermore, is not only magnificent but, as was Alexander in Pliny’s story, also magnanimous, as well. Ultimately, these readings of the Birth of Venus flatter not only the Medici and Botticelli but all of Florence, home to the worthy successors to some of the greatest figures of antiquity, both in governance and in the arts.[43]

These essentially pagan readings of Botticelli’s Birth of Venus should not exclude a more purely Christian one, which may be derived from the Neoplatonic reading of the painting indicated above. Viewed from a religious standpoint, the nudity of Venus suggests that of Eve before the Fall as well as the pure love of Paradise. Once landed, the goddess of love will don the earthly garb of mortal sin, an act that will lead to the New Eve – the Madonna whose purity is represented by the nude Venus. Once draped in earthly garments she becomes a personification of the Christian Church which offers a spiritual transport back to the pure love of eternal salvation. In this case the scallop shell upon which this image of Venus/Eve/Madonna/Church stands may be seen in its traditionally symbolic pilgrimage context. Furthermore, the broad expanse of sea serves as a reminder of the Virgin Mary’s title stella maris, alluding both to the Madonna’s name (Maria/maris) and to the heavenly body (Venus/stella). The sea brings forth Venus just as the Virgin gives birth to the ultimate symbol of love, Christ.[44]

Calumny of Apelles, 1494–95, with “Truth” at left. Uffizi, Florence.

Rather than choosing one of the many interpretations offered for Botticelli’s depiction of the Birth (Arrival?) of Venus it might be better to view it from a variety of perspectives. This layered approach—mythological, political, religious—was intended.[45]

Derivative versions[edit]

Berlin Venus, workshop of Botticelli. Gemäldegalerie, Berlin.

Botticelli, or more likely his workshop, repeated the figure of Venus in another painting of about 1490. This life-sized work depicts a similar figure and pose, partially clad in a light blouse, and contrasted against a plain dark background. It is in the Galleria Sabauda in Turin.[46][47] There is another such workshop Venus in Berlin, and very likely others were destroyed in the “Bonfire of the Vanities”. Examples seem to have been exported to France and Germany, probably influencing Lucas Cranach the Elder among others.[48]

More than a decade later, Botticelli adapted the figure of Venus for a nude personification of “Truth” in his Calumny of Apelles. Here one hand is raised, pointing to heaven for justification, and the figure’s gaze also looks upwards; the whole effect is very different.[49]

Notes[edit]

  • ^ Ettlingers, 134; Legouix, 118
  • ^ Ettlingers, 135–136; Lightbown, 160–162
  • ^ For classical examples, see below. Scallops were familiar Italian seafood, but their shells are never more than a few inches wide. The main European species eaten are Pecten maximus and Pecten jacobaeus in the Mediterranean Sea. No Mediterranean shell is anything like this large, although various tropical giant clam species may reach half this width or more, with a rather different shape.
  • ^ Lightbown, 153–156; 159; Wind, 131
  • ^ Lightbown, 156
  • ^ Lightbown, 156–159; Wind, 131
  • ^ Dempsey uses these identifications. Legouix, 21 argues for the traditional one for the female held by Zephyr.
  • ^ Wind, 115–117
  • ^ Lightbown, 159–160
  • ^ Lightbown, 153
  • ^ Lightbown, 153, 162–163, 163 quoted
  • ^ Lightbown, 162
  • ^ Hemsoll, 2:50
  • ^ Clark, 97–98, 98 quoted; Ettlingers, 134
  • ^ a b c “Botticelli’s Birth of Venus”. Smarthistory at Khan Academy. Retrieved December 19, 2012. 
  • ^ Hemsoll, 18:15
  • ^ Clerk, 281–282
  • ^ Ettlingers, 134
  • ^ Lightbown, 323, note 11
  • ^ Lightbown, 120–122
  • ^ Lightbown, 122 (Primavera in the 1499 inventory), 152. In addition, the writer on art known as the “Anonimo Gaddiano”, from around 1540, speaks of “several” very fine Botticellis at Castello, which may confirm the Birth was there.
  • ^ Lightbown, 122, 153; Hartt, 333
  • ^ Dempsey, Legouix, 115, 118
  • ^ Legouix, 115–118
  • ^ Among many interpretations start with: Aby Warburg, The Renewal of Pagan Antiquity, trans. David Britt, Los Angeles, 1999, 405–431; Ernst H. Gombrich, “Botticelli’s Mythologies: A Study in the Neoplatonic Symbolism of his circle,” Journal of the Warburg and Courtauld Institutes, 8 (1945) 7–60; Wind, Chapter VIII; Lightbown, 152–163; Frank Zollner, Botticelli: Images of Love and Spring, Munich, 1998, 82–91.
  • ^ Dempsey, saying Wind is “the most important and complete Neo-Platonic interpretation of Botticelli’s mythological paintings”.
  • ^ Wind, Chapter VIII (Chapter VII on the Primavera); Stokstad, Marilyn Art History, Pearson
  • ^ Plato, Symposium, 180–181, 210.
  • ^ Hemsoll, 12:00; Hartt, 333
  • ^ James Hankins, “The Myth of the Platonic Academy of Florence,” Renaissance Quarterly, 44 (1991) 429–475.
  • ^ Lilian Zirpolo, “Botticelli’s Primavera: a Lesson for the Bride,” Woman’s Art Journal, 12/2 1991; Jane C. Long, “Botticelli’s Birth of Venus as Wedding Painting,” Aurora, 9 (2008) 1–26.
  • ^ More clearly in the Latin Florentia (“flowering”) than in the Italian Firenze. This was a Roman imperial rename, the city having originally been Fluentia, for its two rivers. Hemsoll, 13:40; Hartt, 333
  • ^ Mack, 2005, 85–86; Lightbown, 160
  • ^ Lightbown, 159–160; Stanze de Messer Angelo Poliziano cominciate per la giostra del magnifico Giuliano di Pietro de Medici, I 99, 101, trans. David L. Quint, University Park, Pennsylvania, 1979.
  • ^ Clark, 97 quoted; see also Ettlingers, 134
  • ^ Hemsoll, 7:40
  • ^ Clark, 92, 96–97; Lightbown, 160, “the first surviving celebration of the beauty of the female nude represented for its own perfection rather than with erotic or moral or religious overtones.”
  • ^ Clark, 76–81; Dempsey
  • ^ Mack, 2005, 86–87
  • ^ Mack (2005), 85–87 and also Mack (2002)
  • ^ See, for example, Frank Zöllner, Sandro Botticelli, Munich, 2005; David Wilkins, A History of Italian Renaissance Art, Upper Saddle River, 2011, neither of whom follow Mack’s interpretation.
  • ^ Mack, 2005, 86
  • ^ Mack, 2005, 87
  • ^ Mack (2002), 225–26
  • ^ Mack (2002), 207, 226
  • ^ Shea, Andrea (April 14, 2017). “What ‘Venus’, Now At The MFA, Can Teach Us About Renaissance Painter Sandro Botticelli”. The ARTery. WBUR-FM. Retrieved 2017-04-24. 
  • ^ “Botticelli and the Search for the Divine”. Museum of Fine Arts, Boston. 19 January 2017. Retrieved 2017-04-24. 
  • ^ Clark, 101–102; Lightbown, 313–315
  • ^ Clark, 99-100; Ettlingers, 145-146
  • References[edit]

    • Clark, Kenneth, The Nude, A Study in Ideal Form, orig. 1949, various edns, page refs from Pelican edn of 1960
    • Dempsey, Charles, “Botticelli, Sandro”, Grove Art Online, Oxford Art Online. Oxford University Press. Web. 15 May. 2017. subscription required.
    • “Ettlingers”: Leopold Ettlinger with Helen S. Ettlinger, Botticelli, 1976, Thames and Hudson (World of Art), ISBN 0500201536
    • Hartt, Frederick, History of Italian Renaissance Art, (2nd edn.)1987, Thames & Hudson (US Harry N Abrams), ISBN 0500235104
    • Hemsoll, David, The Birth of Venus, University of Birmingham, 18 min introductory lecture, refs to mm:ss
    • Legouix, Susan, Botticelli, 115–118, 2004 (revd edn), Chaucer Press, ISBN 1904449212
    • Lightbown, Ronald, Sandro Botticelli: Life and Work, 1989, Thames and Hudson
    • Mack, Charles R. (2002),”Botticelli’s Venus: Antique Allusions and Medicean Propaganda,” Explorations in Renaissance Culture, 28, 1 (Winter), 2002, 1–31.
    • Mack, Charles R. (2005), Looking at the Renaissance: Essays toward a Contextual Appreciation, Ann Arbor: University of Michigan Press, 2005
    • Wind, Edgar, Pagan Mysteries in the Renaissance, 1967 edn., Peregrine Books

    External links[edit]

    • University of Birmingham: Dr David Hemsoll, The Birth of Venus – mini-lecture
    • ArtSleuth: The Birth of Venus – That Obscure Object of Desire


    Birth problem

    This article is about congenital disorders in humans. For animals, see Teratology.

    A birth defect, also known as a congenital disorder, is a condition present at birth regardless of its cause.[3] Birth defects may result in disabilities that may be physical, intellectual, or developmental.[3] The disabilities can range from mild to severe.[7] Birth defects are divided into two main types: structural disorders in which there are problems with the shape of a body part and functional disorders in which there are problems with how a body part works.[4] Functional disorders include metabolic and degenerative disorders.[4] Some birth defects include both structural and functional disorders.[4]

    Birth defects may result from genetic or chromosomal disorders, exposure to certain medications or chemicals, or certain infections during pregnancy.[5] Risk factors include folate deficiency, drinking alcohol or smoking during pregnancy, poorly controlled diabetes, and a mother over the age of 35 years old.[6][7] Many are believed to involve multiple factors.[7] Birth defects may be visible at birth or diagnosed by screening tests.[10] A number of defects can be detected before birth by different prenatal tests.[10]

    Treatment varies depending on the defect in question.[8] This may include therapy, medication, surgery, or assistive technology.[8] Birth defects affected about 96 million people as of 2015.[11] In the United States they occur in about 3% of newborns.[2] They resulted in about 628,000 deaths in 2015 down from 751,000 in 1990.[12][9] The types with the greatest numbers of deaths are congenital heart disease (303,000), followed by neural tube defects (65,000).[9]

    Contents

    • 1 Classification
      • 1.1 Primarily structural
        • 1.1.1 Terminology
        • 1.1.2 Examples of primarily structural congenital disorders
      • 1.2 Primarily metabolic
      • 1.3 Other
    • 2 Causes
      • 2.1 Fetal alcohol exposure
      • 2.2 Toxic substances
        • 2.2.1 Medications and supplements
        • 2.2.2 Toxic substances
      • 2.3 Smoking
      • 2.4 Infections
      • 2.5 Lack of nutrients
      • 2.6 Physical restraint
      • 2.7 Genetic causes
      • 2.8 Socioeconomic status
      • 2.9 Radiation
      • 2.10 Parent’s age
      • 2.11 Unknown
    • 3 Screening
    • 4 Epidemiology
      • 4.1 United States
    • 5 See also
    • 6 References
    • 7 External links

    Classification[edit]

    Much of the language used for describing congenital conditions predates genome mapping, and structural conditions are often considered separately from other congenital conditions. It is now known that many metabolic conditions may have subtle structural expression, and structural conditions often have genetic links. Still, congenital conditions are often classified in a structural basis, organized when possible by primary organ system affected.[citation needed]

    Primarily structural[edit]

    Several terms are used to describe congenital abnormalities. (Some of these are also used to describe noncongenital conditions, and more than one term may apply in an individual condition.)

    Terminology[edit]

    • A congenital physical anomaly is an abnormality of the structure of a body part. An anomaly may or may not be perceived as a problem condition. Many, if not most, people have one or more minor physical anomalies if examined carefully. Examples of minor anomalies can include curvature of the 5th finger (clinodactyly), a third nipple, tiny indentations of the skin near the ears (preauricular pits), shortness of the 4th metacarpal or metatarsal bones, or dimples over the lower spine (sacral dimples). Some minor anomalies may be clues to more significant internal abnormalities.
    • Birth defect is a widely used term for a congenital malformation, i.e. a congenital, physical anomaly which is recognizable at birth, and which is significant enough to be considered a problem. According to the CDC, most birth defects are believed to be caused by a complex mix of factors including genetics, environment, and behaviors,[13] though many birth defects have no known cause. An example of a birth defect is cleft palate, which occurs during the fourth and seventh week of gestation.[14] Body tissue and special cells from each side of the head grow toward the center of the face. They join together to make the face.[14] A cleft means a split or separation; the “roof” of the mouth is called the palate.[15]
    • A congenital malformation is a congenital physical anomaly that is deleterious, i.e. a structural defect perceived as a problem. A typical combination of malformations affecting more than one body part is referred to as a malformation syndrome.
    • Some conditions are due to abnormal tissue development:
      • A malformation is associated with a disorder of tissue development.[16] Malformations often occur in the first trimester.
      • A dysplasia is a disorder at the organ level that is due to problems with tissue development.[16]
    • It is also possible for conditions to arise after tissue is formed:
      • A deformation is a condition arising from mechanical stress to normal tissue.[16] Deformations often occur in the second or third trimester, and can be due to oligohydramnios.
      • A disruption involves breakdown of normal tissues.[16]
    • When multiple effects occur in a specified order, it is known as a sequence. When the order is not known, it is a syndrome.

    Examples of primarily structural congenital disorders[edit]

    A limb anomaly is called a dysmelia. These include all forms of limbs anomalies, such as amelia, ectrodactyly, phocomelia, polymelia, polydactyly, syndactyly, polysyndactyly, oligodactyly, brachydactyly, achondroplasia, congenital aplasia or hypoplasia, amniotic band syndrome, and cleidocranial dysostosis.

    Congenital anomalies of the heart include patent ductus arteriosus, atrial septal defect, ventricular septal defect, and tetralogy of fallot.

    Congenital anomalies of the nervous system include neural tube defects such as spina bifida, encephalocele and anencephaly. Other congenital anomalies of the nervous system include the Arnold-Chiari malformation, the Dandy-Walker malformation, hydrocephalus, microencephaly, megalencephaly, lissencephaly, polymicrogyria, holoprosencephaly, and agenesis of the corpus callosum.

    Congenital anomalies of the gastrointestinal system include numerous forms of stenosis and atresia, and perforation, such as gastroschisis.

    Congenital anomalies of the kidney and urinary tract (CAKUT) include renal parenchyma, kidneys, and urinary collecting system.[17]

    Defects can be bilateral or unilateral, and different defects often coexist in an individual child.

    Primarily metabolic[edit]

    Main article: Inborn error of metabolism

    A congenital metabolic disease is also referred to as an inborn error of metabolism. Most of these are single gene defects, usually heritable. Many affect the structure of body parts but some simply affect the function.

    Other[edit]

    Other well defined genetic conditions may affect the production of hormones, receptors, structural proteins, and ion channels.

    Causes[edit]

    Fetal alcohol exposure[edit]

    Main articles: Fetal alcohol spectrum disorder and Fetal alcohol syndrome

    The mother’s consumption of alcohol during pregnancy can cause a continuum of various permanent birth defects : cranofacial abnormalities,[18] brain damage,[19] intellectual disability,[20] heart disease, kidney abnormality, skeletal anomalies, ocular abnormalities.[21]

    The prevalence of children affected is estimated at least 1 percent in U.S.[22] as well in Canada.

    Very few studies have investigated the links between paternal alcohol use and offspring health.[23]

    However, recent animal research has shown a correlation between paternal alcohol exposure and decreased offspring birth weight. Behavioral and cognitive disorders, including difficulties with learning and memory, hyperactivity, and lowered stress tolerance have been linked to paternal alcohol ingestion. The compromised stress management skills of animals whose male parent was exposed to alcohol are similar to the exaggerated responses to stress that children with fetal alcohol syndrome display because of maternal alcohol use. These birth defects and behavioral disorders were found in cases of both long- and short-term paternal alcohol ingestion.[24][25] In the same animal study, paternal alcohol exposure was correlated with a significant difference in organ size and the increased risk of the offspring displaying ventricular septal defects at birth.[25]

    Toxic substances[edit]

    Further information: Developmental toxicity, Drugs in pregnancy, and Environmental toxins and fetal development

    Substances whose toxicity can cause congenital disorders are called teratogens, and include certain pharmaceutical and recreational drugs in pregnancy as well as many environmental toxins in pregnancy.[citation needed]

    A review published in 2010 identified 6 main teratogenic mechanisms associated with medication use: folate antagonism, neural crest cell disruption, endocrine disruption, oxidative stress, vascular disruption and specific receptor- or enzyme-mediated teratogenesis.[26]

    It is estimated that 10% of all birth defects are caused by prenatal exposure to a teratogenic agent.[27] These exposures include, but are not limited to, medication or drug exposures, maternal infections and diseases, and environmental and occupational exposures. Paternal smoking use has also been linked to an increased risk of birth defects and childhood cancer for the offspring, where the paternal germline undergoes oxidative damage due to cigarette use.[28][29] Teratogen-caused birth defects are potentially preventable. Studies have shown that nearly 50% of pregnant women have been exposed to at least one medication during gestation.[30] During pregnancy, a female can also be exposed to teratogens from the contaminated clothing or toxins within the seminal fluid of a partner.[31][24][32] An additional study found that of 200 individuals referred for genetic counseling for a teratogenic exposure, 52% were exposed to more than one potential teratogen.[33]

    Medications and supplements[edit]

    Probably, the most well-known teratogenic drug is thalidomide. It was developed near the end of the 1950s by Chemie Grűnenthal as a sleep inducing aid and antiemetic. Because of its ability to prevent nausea it was prescribed for pregnant women in almost 50 countries worldwide between 1956–1962.[34] Until William McBride published the study leading to its withdrawal from the market at 1961, about 8- 10 000 severely malformed children were born. The most typical disorder induced by thalidomide were reductional deformities of the long bones of the extremities. Phocomelia otherwise a rare deformity, which therefore helped to recognise the teratogenic effect of the new drug. Among other malformations caused by thalidomide were those of ears, eyes, brain, kidney, heart, digestive and respiratory tract. 40% of the prenatally affected children died soon after birth.[34] As thalidomide is used today as a treatment for multiple myeloma and leprosy, several births of affected children were described in spite of the strictly required use of contraception among female patients treated by it.

    Vitamin A, is the sole vitamin which is embryotoxic even in a therapeutic dose, for example in multivitamins, because its metabolite retinoic acid, plays an important role as a signal molecule in the development of several tisues and organs. Its natural precursor, β-carotene, is considered safe, whereas the consumption of animal liver can lead to malformation, as the liver stores lipophile vitamins, including retinol.[34] Isotretinoin (13-cis-retinoic-acid; brand name Roaccutane), vitamine A analog, which is often used to treat severe acne, is such a strong teratogen that just a single dose taken by a pregnant woman (even transdermally) may result in serious birth defects. Because of this effect, most countries have systems in place to ensure that it is not given to pregnant women, and that the patient is aware of how important it is to prevent pregnancy during and at least one month after treatment. Medical guidelines also suggest that pregnant women should limit vitamin A intake to about 700 μg/day, as it has teratogenic potential when consumed in excess.[35][36] Vitamine A and similar substances can induce spontaneous abortions, premature births, defects of eyes (microphthalmia), ears, thymus, face deformities, neurological (hydrocephalus, microcephalia) and cardiovascular defects, as well as mental retardation.[34]

    Tetracycline, an antibiotic, should never be prescribed to women of reproductive age or to children, because of its negative impact on bone mineralization and teeth mineralization. The “tetracycline teeth” have brown or grey colour as a result of a defective development of both the dentine and the enamel of teeth.[34]

    Several anticonvulsants are known to be highly teratogenic. Phenytoin, also known as diphenylhydantoin, along with carbamazepine is responsible for the fetal hydantoin syndrome, which may typically include broad nose base, cleft lip and/or palate, microcephalia, nails and fingers hypoplasia, intrauterine growth restriction and mental retardation. Trimethadione taken during pregnancy is responsible for the fetal trimethadione syndrome, characterized by craniofacial, cardiovascular, renal and spine malformations, along with a delay in mental and physical development. Valproate has antifolate effects, leading to neural tube closure-related defects such as spina bifida. Lower IQ and autism have recently also been reported as a result of intrauterine valproate exposure.[34]

    Hormonal contraception is considered as harmless for the embryo. Peterka and Novotná[34] do however state that syntethic progestines used to prevent miscarriage in the past frequently caused masculinization of the outer reproductive organs of female newborns due to their androgenic activity. Diethylstilbestrol is a synthetic estrogen used from the 1940s to 1971 when the prenatal exposition has been linked to the clear-cell adenocarcinoma of the vagina. Following studies showed elevated risks for other tumors and congenital malformations of the sex organs for both sexes.

    All cytostatics are strong teratogens, abortion is usually recommended when pregnancy is discovered during or before chemotherapy. Aminopterin, a cytostatic drug with anti-folate effect, was used during the 1950s and 1960s to induce therapeutic abortions. In some cases the abortion didn´t happen, but the newborns suffered a fetal aminopterin syndrome consisting of growth retardation, craniosynostosis, hydrocephalus, facial dismorphities, mental retardation and/or leg defomities[34][37]

    Toxic substances[edit]

    Drinking water is often a medium through which harmful toxins travel. Studies have shown that heavy metals, elements, nitrates, nitrites, fluoride can be carried through water and cause congenital disorders.

    Nitrate, which is found mostly in drinking water from ground sources, is a powerful teratogen. A case-control study in rural Australia that was conducted following frequent reports of prenatal mortality and congenital malformations found that those who drank the nitrate-infected groundwater, as opposed to rain water, ran the risk of giving birth to children with central nervous system disorders, muscoskeletal defects, and cardiac defects.[38]

    Chlorinated and aromatic solvents such as benzene and trichloroethylene sometimes enter the water supply due to oversights in waste disposal. A case-control study on the area found that by 1986, leukemia was occurring in the children of Woburn, Massachusetts at a rate that was four times the expected rate of incidence. Further investigation revealed a connection between the high occurrence of leukemia and an error in water distribution that delivered water to the town with significant contamination manufacturing waste containing trichloroethylene.[39] As an endocrine disruptor, the DDT was shown to induce miscarriages, interfere with the development of the female reproductive system, cause the congenital hypothyroidism and suspectibly childhood obesity.[34]

    Fluoride, when transmitted through water at high levels, can also act as a teratogen. Two reports on fluoride exposure from China, which were controlled to account for the education level of parents, found that children born to parents who were exposed to 4.12 PPM fluoride grew to have IQs that were, on average, seven points lower than their counterparts whose parents consumed water that contained 0.91 PPM fluoride. In studies conducted on rats, higher PPM fluoride in drinking water lead to increased acetylcholinesterase levels, which can alter prenatal brain development. The most significant effects were noted at a level of 5 PPM.[40]

    The fetus is even more susceptible to damage from carbon monoxide intake, which can be harmful when inhaled during pregnancy, usually through first or second-hand tobacco smoke. The concentration of carbon monoxide in the infant born to a non-smoking mother is around 2%, and this concentration drastically increases to a range of 6%–9% if the mother smokes tobacco. Other possible sources of prenatal carbon monoxide intoxication are exhaust gas from combustion motors, use of dichloromethane (paint thinner, varnish removers) in enclosed areas, defective gas hot water heaters, indoor barbeques, open flames in poorly-ventilated areas, atmospheric exposure in highly polluted areas. Exposure to carbon monoxide at toxic levels during the first two trimesters of pregnancy can lead to intrauterine growth restriction, leading to a baby that has stunted growth and is born smaller than 90% of other babies at the same gestational age. The effect of chronic exposure to carbon monoxide can depend on the stage of pregnancy in which the mother is exposed. Exposure during the embryonic stage can have neurological consequences, such as telencephalic dysgenesis, behavioral difficulties during infancy, and reduction of cerebellum volume. There are also possible skeletal defects that could result from exposure to carbon monoxide during the embryonic stage, such as hand and foot malformations, hip dysplasia, hip subluxation, agenisis of a limb, and inferior maxillary atresia with glossoptosis. Also, carbon monoxide exposure between days 35 and 40 of embryonic development can lead to an increased risk of the child developing a cleft palate. Exposure to carbon monoxide or polluted ozone exposure can also lead to cardiac defects of the ventrical septal, pulmonary artery and heart valves.[41] The effects of carbon monoxide exposure are decreased later in fetal development during the fetal stage, but they may still lead to anoxic encephalopathy.[42]

    Industrial pollution can also lead to congenital defects. Over a period of 37 years, the Chisso Corporation, a petrochemical and plastics company, contaminated the waters of Minamata Bay with an estimated 27 tons of methylmercury, contaminating the local water supply. This led to many people in the area developing what became known as the “Minamata Disease.” Because methylmercury is a teratogen, the mercury poisoning of those residing by the bay resulted in neurological defects in the offspring. Infants exposed to mercury poisoning in utero showed predispositions to cerebral palsy, ataxia, inhibited psychomotor development, and mental retardation.[43]

    Landfill sites have been shown to have adverse effects on fetal development. Extensive research has been shown that landfills have several negative effects on babies born to mothers living near landfill sites: low birth weight, birth defects, spontaneous abortion, and fetal and infant mortality. Studies done around the Love Canal site near Niagara Falls and the Lipari Landfill in New Jersey have shown a higher proportion of low birth babies than communities farther away from landfills. A study done in California showed a positive correlation between time and quantity of dumping and low birth weights and neonatal deaths. A study in the United Kingdom showed a correspondence between pregnant women living near landfill sites and an increased risk of congenital disorders, such as neural tube defects, hypospadias, epispadia, and abdominal wall defects, such as gastroschisis and exomphalos. A study conducted on a Welsh community also showed an increase incidence of gastroschisis. Another study was done on twenty-one European hazardous waste sites and showed that those living within three kilometers had an increased risk of giving birth to infants with birth defects and that as distance from the land increased, the risk decreased. These birth defects included neural tube defects, malformations of the cardiac septa, anomalies of arteries and veins, and chromosomal anomalies.[44] Looking at communities that live near landfill sites brings up environmental justice. A vast majority of sites are located near poor, mostly black, communities. For example, between the early 1920s and 1978, about 25% of Houston’s population was black. However, over 80% of landfills and incinerators during this time were located in these black communities.[45]

    Another issue regarding environmental justice is lead poisoning. If the fetus is exposed to lead during the pregnancy, this can result in learning difficulties and slowed growth. A lot of paints (before 1978) and pipes contain lead. Therefore, pregnant women who live in homes with lead paint will inhale the dust containing lead, leading to lead exposure in the fetus. When lead pipes are used for drinking water and cooking water, this water is ingested, along with the lead, exposing the fetus to this toxin. This issue is more prevalent in poorer communities. This is because more well off families are able to afford to have their homes repainted and pipes renovated.[46]

    Smoking[edit]

    Paternal smoking prior to conception has been linked with the increased risk of congenital abnormalities in offspring.[23]

    Smoking causes DNA mutations in the germline of the father, which can be inherited by the offspring. Cigarette smoke acts as a chemical mutagen on germ cell DNA. The germ cells suffer oxidative damage, and the effects can be seen in altered mRNA production, infertility issues, and side effects in the embryonic and fetal stages of development. This oxidative damage may result in epigenetic or genetic modifications of the father’s germline. Research has shown that fetal lymphocytes have been damaged as a result of a father’s smoking habits prior to conception.[31][29]

    Correlations between paternal smoking and the increased risk of offspring developing childhood cancers (including acute leukemia, brain tumors, and lymphoma) before age five have been established. However, further research is needed to confirm these findings. Little is currently known about how paternal smoking damages the fetus, and what window of time in which the father smokes is most harmful to offspring.[29]

    Infections[edit]

    Main article: Vertically transmitted infection

    A vertically transmitted infection is an infection caused by bacteria, viruses or, in rare cases, parasites transmitted directly from the mother to an embryo, fetus or baby during pregnancy or childbirth. It can occur when the mother gets an infection as an intercurrent disease in pregnancy.

    Congenital disorders were initially believed to be the result of only hereditary factors. However, in the early 1940s, Australian pediatric ophthalmologist Norman Gregg began recognizing a pattern in which the infants arriving at his surgery were developing congenital cataracts at a higher rate than those who developed it from hereditary factors. On October 15, 1941, Gregg delivered a paper which explained his findings-68 out of the 78 children who were afflicted with congenital cataracts had been exposed in utero to rubella due to an outbreak in Australian army camps. These findings confirmed, to Gregg, that there could, in fact, be environmental causes for congenital disorders.

    Rubella is known to cause abnormalities of the eye, internal ear, heart, and sometimes the teeth. More specifically, fetal exposure to rubella during weeks five to ten of development (the sixth week particularly) can cause cataracts and microphthalmia in the eyes. If the mother is infected with rubella during the ninth week, a crucial week for internal ear development, there can be destruction of the organ of Corti, causing deafness. In the heart the ductus arteriosus can remain after birth, leading to hypertension. Rubella can also lead to atrial and ventricular septal defects in the heart. If exposed to rubella in the second trimester, the fetus can develop central nervous system malformations. However, because infections of rubella may remain undetected, misdiagnosed, or unrecognized in the mother, and/or some abnormalities are not evident until later in the child’s life, precise incidence of birth defects due to rubella are not entirely known. The timing of the mother’s infection during fetal development determines the risk and type of birth defect. As the embryo develops, the risk of abnormalities decreases. If exposed to the rubella virus during the first four weeks, the risk of malformations is 47 percent. Exposure during weeks five through eight creates a 22 percent chance, while weeks nine to twelve a seven percent chance exists, followed by a percentage of six if the exposure is during the thirteenth to sixteenth weeks. Exposure during the first eight weeks of development can also lead to prematurity and fetal death. These numbers are calculated from immediate inspection of the infant after birth. Therefore, mental defects are not accounted for in the percentages because they are not evident until later in the child’s life. If they were to be included, these numbers would be much higher.[47]

    Other infectious agents include cytomegalovirus, the herpes simplex virus, hyperthermia, toxoplasmosis, and syphilis. Mother exposure to cytomegalovirus can cause microcephaly, cerebral calcifications, blindness, chorioretinitis (which can cause blindness), hepatosplenomegaly, and meningoencephalitis in fetuses.[47] Microcephaly is a disorder in which the fetus has an atypically small head,[48] cerebral calcifications means certain areas of the brain have atypical calcium deposits,[49] and meningoencephalitis is the enlargement of the brain. All three disorders cause abnormal brain function or mental retardation. Hepatosplenomegaly is the enlargement of the liver and spleen which causes digestive problems.[50] It can also cause some kernicterus and petechiae. Kernicterus causes yellow pigmentation of the skin, brain damage, and deafness.[51] Petechaie is when the capillaries bleed resulting in red/purple spots on the skin.[52] However, cytomegalovirus is often fatal in the embryo.

    The herpes simplex virus can cause microcephaly, microphthalmus (abnormally small eyeballs),[53] retinal dysplasia, hepatosplenomegaly, and mental retardation.[47] Both microphthalmus and retinal dysplasia can cause blindness. However, the most common symptom in infants is an inflammatory response that develops during the first three weeks of life.[47] Hyperthermia causes anencephaly, which is when part of the brain and skull are absent in the infant.[47][54] Mother exposure to toxoplasmosis can cause cerebral calcification, hydrocephalus (causes mental disabilities),[55] and mental retardation in infants. Other birth abnormalities have been reported as well, such as chorioretinitis, microphthalmus, and ocular defects. Syphilis causes congenital deafness, mental retardation, and diffuse fibrosis in organs, such as the liver and lungs, if the embryo is exposed.[47]

    Lack of nutrients[edit]

    Further information: Nutrition in pregnancy

    For example, a lack of folic acid, a vitamin B, in the diet of a mother can cause cellular neural tube deformities that result in spina bifida. Congenital disorders such as a neural tube deformity (NTD) can be prevented by 72% if the mother consumes 4 milligrams of folic acid before the conception and after 12 weeks of pregnancy.[56] Folic acid, or vitamin B9, aids the development of the foetal nervous system.[56]

    Studies with mice have found that food deprivation of the male mouse prior to conception leads to the offspring displaying significantly lower blood glucose levels.[57]

    Physical restraint[edit]

    External physical shocks or constrainment due to growth in a restricted space, may result in unintended deformation or separation of cellular structures resulting in an abnormal final shape or damaged structures unable to function as expected. An example is Potter syndrome due to oligohydramnios. This finding is important for future understandings of how genetics may predispose individuals for diseases like obesity, diabetes, and cancer.

    For multicellular organisms that develop in a womb, the physical interference or presence of other similarly developing organisms such as twins can result in the two cellular masses being integrated into a larger whole, with the combined cells attempting to continue to develop in a manner that satisfies the intended growth patterns of both cell masses. The two cellular masses can compete with each other, and may either duplicate or merge various structures. This results in conditions such as conjoined twins, and the resulting merged organism may die at birth when it must leave the life-sustaining environment of the womb and must attempt to sustain its biological processes independently.

    Genetic causes[edit]

    Main article: Genetic disorder
    See also: List of genetic disorders

    Genetic causes of congenital anomalies include inheritance of abnormal genes from the mother or the father, as well as new mutations in one of the germ cells that gave rise to the fetus. Male germ cells mutate at a much faster rate than female germ cells, and as the father ages, the DNA of the germ cells mutates quickly.[58][28] If an egg is fertilized with sperm that has damaged DNA, there is a possibility that the fetus could develop abnormally.[58][59]

    Genetic disorders or diseases are all congenital, though they may not be expressed or recognized until later in life. Genetic diseases may be divided into single-gene defects, multiple-gene disorders, or chromosomal defects. Single-gene defects may arise from abnormalities of both copies of an autosomal gene (a recessive disorder) or of only one of the two copies (a dominant disorder). Some conditions result from deletions or abnormalities of a few genes located contiguously on a chromosome. Chromosomal disorders involve the loss or duplication of larger portions of a chromosome (or an entire chromosome) containing hundreds of genes. Large chromosomal abnormalities always produce effects on many different body parts and organ systems.

    Socioeconomic status[edit]

    A low socioeconomic status in a deprived neighborhood may include exposure to “environmental stressors and risk factors.”[60] Socioeconomic inequalities are commonly measured by the Cartairs-Morris score, Index of Multiple Deprivation, Townsend deprivation index, and the Jarman score.[61] The Jarman score, for example, considers “unemployment, overcrowding, single parents, under-fives, elderly living alone, ethnicity, low social class and residential mobility.”[61] In Vos’ meta-analysis these indices are used to view the effect of low SES neighborhoods on maternal health. In the meta-analysis, data from individual studies were collected from 1985 up until 2008.[61] Vos concludes that a correlation exists between prenatal adversities and deprived neighborhoods.[61] Other studies have shown that low SES is closely associated with the development of the fetus in utero and growth retardation.[62] Studies also suggest that children born in low SES families are “likely to be born prematurely, at low birth weight, or with asphyxia, a birth defect, a disability, fetal alcohol syndrome, or AIDS.”[62] Bradley and Corwyn also suggest that congenital disorders arise from the mother’s lack of nutrition, a poor lifestyle, maternal substance abuse and “living in a neighborhood that contains hazards affecting fetal development (toxic waste dumps).”[62] In a meta-analysis that viewed how inequalities influenced maternal health, it was suggested that deprived neighborhoods often promoted behaviors such as smoking, drug and alcohol use.[60] After controlling for socioeconomic factors and ethnicity, several individual studies demonstrated an association with outcomes such as perinatal mortality and preterm birth.[60]

    Radiation[edit]

    For the survivors of the atomic bombing of Hiroshima and Nagasaki, who are known as the Hibakusha, no statistically demonstrable increase of birth defects/congenital malformations was found among their later conceived children, or found in the later conceived children of cancer survivors who had previously received radiotherapy.[63][64][65] [66] The surviving women of Hiroshima and Nagasaki who were able to conceive, though exposed to substantial amounts of radiation, later had children with no higher incidence of abnormalities/birth defects than in the Japanese population as a whole.[67][68]

    Relatively few studies have researched the effects of paternal radiation exposure on offspring. Following the Chernobyl disaster, it was assumed in the 1990s that the germ line of irradiated fathers suffered minisatellite mutations in the DNA, which was inherited by descendants.[24][69] more recently however, the World Health Organization states, “children conceived before or after their father’s exposure showed no statistically significant differences in mutation frequencies”.[70] This statistically insignificant increase was also seen by independent researchers analyzing the children of the liquidators.[71] Animal studies have shown that incomparably massive doses of X-ray irradiation of male mice resulted in birth defects of the offspring.[31]

    In the 1980s, a relatively high prevalence of pediatric leukemia cases in children living near a nuclear processing plant in West Cumbria, UK, led researchers to investigate whether the cancer was a result of paternal radiation exposure. A significant association between paternal irradiation and offspring cancer was found, but further research areas close to other nuclear processing plants did not produce the same results.[31][24] Later this was determined to be the Seascale cluster in which the leading hypothesis is the influx of foreign workers, who have a different rate of leukemia within their race than the British average, resulted in the observed cluster of 6 children more than expected around Cumbria.[72]

    Parent’s age[edit]

    Main articles: Advanced maternal age and Paternal age effect

    Certain birth complications can occur more often in advanced maternal age (greater than 35 years). Complications include fetal growth restriction, preeclampsia, placental abruption, pre-mature births, and stillbirth. These complications not only may put the child at risk, but also the mother.[73]

    The effects of the fathers age on offspring are not yet well understood and are studied far less extensively than the effects of the mother’s age.[74] Fathers contribute proportionally more DNA mutations to their offspring via their germ cells than the mother, with the paternal age governing how many mutations are passed on. This is because, as humans age, male germ cells acquire mutations at a much faster rate than female germ cells.[58][31][28]

    Around a 5% increase in the incidence of ventricular septal defects, atrial septal defects, and patent ductus arteriosus in offspring has been found to be correlated with advanced paternal age. Advanced paternal age has also been linked to increased risk of achondroplasia and Apert syndrome. Offspring born to fathers under the age of 20 show increased risk of being affected by patent ductus arteriosus, ventricular septal defects, and the tetralogy of Fallot. It is hypothesized that this may be due to environmental exposures or lifestyle choices.[74]

    Research has found that there is a correlation between advanced paternal age and risk of birth defects such as limb anomalies, syndromes involving multiple systems, and Down’s syndrome.[58][28][75] Recent studies have concluded that 5-9% of Down’s syndrome cases are due to paternal effects, but these findings are controversial.[58][59][28][76]

    There is concrete evidence that advanced paternal age is associated with the increased likelihood that a mother will have a miscarriage or that fetal death will occur.[58]

    Unknown[edit]

    Although significant progress has been made in identifying the etiology of some birth defects, approximately 65% have no known or identifiable cause.[27] These are referred to as sporadic, a term that implies an unknown cause, random occurrence regardless of maternal living conditions,[77] and a low recurrence risk for future children. For 20-25% of anomalies there seems to be a “multifactorial” cause, meaning a complex interaction of multiple minor genetic anomalies with environmental risk factors. Another 10–13% of anomalies have a purely environmental cause (e.g. infections, illness, or drug abuse in the mother). Only 12–25% of anomalies have a purely genetic cause. Of these, the majority are chromosomal anomalies.[78]

    Screening[edit]

    Newborn screening tests were introduced in the early 1960s and initially dealt with just two disorders. Since then tandem mass spectrometry, gas chromatography–mass spectrometry , and DNA analysis has made it possible for a much larger range of disorders to be screened. Newborn screening mostly measures metabolite and enzyme activity using a dried blood spot sample.[79] Screening tests are carried out in order to detect serious disorders that may be treatable to some extent.[80] Early diagnosis makes possible the readiness of therapeutic dietary information, enzyme replacement therapy and organ transplants.[81] Different countries support the screening for a number of metabolic disorders (inborn errors of metabolism (IEM)), and genetic disorders including cystic fibrosis and Duchenne muscular dystrophy.[80][82] Tandem mass spectroscopy can also be used for IEM, and investigation of sudden infant death, and shaken baby syndrome.[80]

    Screening can also be carried out prenatally and can include obstetric ultrasonography to give scans such as the nuchal scan. 3D ultrasound scans can give detailed information of structural anomalies.

    Epidemiology[edit]

    Congenital anomalies deaths per million persons in 2012

      0–26
      27–34
      35–46
      47–72
      73–91
      92–111
      112–134
      135–155
      156–176
      177–396

    Disability-adjusted life year for congenital anomalies per 100,000 inhabitants in 2004.[83]

      no data
      less than 160
      160–240
      240–320
      320–400
      400–480
      480–560
      560–640
      640–720
      720–800
      800–900
      900–950
      more than 950

    Congenital anomalies resulted in about 632,000 deaths per year in 2013 down from 751,000 in 1990.[12] The types with the greatest death are congenital heart defects (323,000), followed by neural tube defects (69,000).[12]

    Many studies have found that the frequency of occurrence of certain congenital malformations depends on the sex of the child (table).[84][85][86][87][88] For example, pyloric stenosis occurs more often in males while congenital hip dislocation is four to five times more likely to occur in females. Among children with one kidney, there are approximately twice as many males, whereas among children with three kidneys there are approximately 2.5 times more females. The same pattern is observed among infants with excessive number of ribs, vertebrae, teeth and other organs which in a process of evolution have undergone reduction—among them there are more females. Contrarily, among the infants with their scarcity, there are more males. Anencephaly is shown to occur approximately twice as frequently in females.[89] The number of boys born with 6 fingers is two times higher than the number of girls.[90] Now various techniques are available to detect congenital anomalies in fetus before birth.[citation needed]

    About 3% of newborns have a “major physical anomaly”, meaning a physical anomaly that has cosmetic or functional significance.[91] Physical congenital abnormalities are the leading cause of infant mortality in the United States, accounting for more than 20% of all infant deaths. Seven to ten percent of all children[clarification needed] will require extensive medical care to diagnose or treat a birth defect.[92]

    • Data[88] obtained on opposite-sex twins. ** — Data[95] were obtained in the period 1983–1994.

    P. M. Rajewski and A. L. Sherman (1976) have analyzed the frequency of congenital anomalies in relation to the system of the organism. Prevalence of men was recorded for the anomalies of phylogenetically younger organs and systems.[93]

    In respect of an etiology, sexual distinctions can be divided on appearing before and after differentiation of male’s gonads in during embryonic development, which begins from eighteenth week. The testosterone level in male embryos thus raises considerably.[97] The subsequent hormonal and physiological distinctions of male and female embryos can explain some sexual differences in frequency of congenital defects. It is difficult to explain the observed differences in the frequency of birth defects between the sexes by the details of the reproductive functions or the influence of environmental and social factors.

    United States[edit]

    The CDC and National Birth Defect Project studied the incidence of birth defects in the US. Key findings include:

    • Down syndrome was the most common condition with an estimated prevalence of 14.47 per 10,000 live births, implying about 6,000 diagnoses each year.
    • About 7,000 babies are born with a cleft palate, cleft lip or both.

    See also[edit]

    • Malformative syndrome
    • ICD-10 Chapter Q: Congenital malformations, deformations and chromosomal abnormalities
    • Idiopathic
    • List of congenital disorders
    • List of ICD-9 codes 740-759: Congenital anomalies
    • March of Dimes
    • Mitochondrial disease
    • Supernumerary body part

    References[edit]

  • ^ Ruth A. Hannon (2010). Porth pathophysiology : concepts of altered health states (1st Canadian ed.). Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins. p. 128. ISBN 978-1-60547-781-7. 
  • ^ a b c “Birth Defects”. Dec 15, 2015. Retrieved 17 Jan 2016. 
  • ^ a b c d “Birth Defects: Condition Information”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ a b c d “What are the types of birth defects?”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ a b “What causes birth defects?”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ a b “How many people are affected by/at risk for birth defects?”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ a b c d “Facts Birth Defects”. Centers for Disease Control and Prevention. 7 September 2017. Retrieved 8 December 2017. 
  • ^ a b c “What are the treatments for birth defects?”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ a b c GBD 2015 Mortality and Causes of Death, Collaborators. (8 October 2016). “Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015: a systematic analysis for the Global Burden of Disease Study 2015”. Lancet. 388 (10053): 1459–1544. doi:10.1016/s0140-6736(16)31012-1. PMC 5388903 . PMID 27733281. 
  • ^ a b “How do health care providers diagnose birth defects?”. www.nichd.nih.gov. Retrieved 8 December 2017. 
  • ^ GBD 2015 Disease and Injury Incidence and Prevalence, Collaborators. (8 October 2016). “Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015”. Lancet. 388 (10053): 1545–1602. doi:10.1016/S0140-6736(16)31678-6. PMC 5055577 . PMID 27733282. 
  • ^ a b c GBD 2013 Mortality and Causes of Death, Collaborators (17 December 2014). “Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013”. Lancet. 385 (9963): 117–71. doi:10.1016/S0140-6736(14)61682-2. PMC 4340604 . PMID 25530442. 
  • ^ Birth Defects Research. Centers for Disease Control and Prevention.
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  • ^ communications. “Cleft Lip and Cleft Palate”. American Academy of Otolaryngology-Head and Neck Surgery. Retrieved 2016-03-16. 
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  • ^ Croen, Lisa; Todoroff, Karen; Shaw, Gary (2001). “Maternal Exposure to Nitrate from Drinking Water and Diet and Risk for Neural Tube Defects”. American Journal of Epidemiology. 153 (4): 325–31. doi:10.1093/aje/153.4.325. PMID 11207149. 
  • ^ Costas, K.; Knorr, R.S.; Condon, S.K. (2002). “A case-control study of childhood leukemia in Woburn, Massachusetts: the relationship between leukemia incidence and exposure to public drinking water”. Science of the Total Environment. 300 (1–3): 23–35. doi:10.1016/s0048-9697(02)00169-9. PMID 12685468. 
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  • ^ Ritz, B.; Yu, F.; Fruin, S.; Chapa, G.; Shaw, G.; Harris, J. (2002). “Ambient Air Pollution and Risk of Birth Defects in Southern California” (PDF). American Journal of Epidemiology. 155 (1): 17–25. doi:10.1093/aje/155.1.17. PMID 11772780. Retrieved 7 December 2014. 
  • ^ Aubard, Yves; Magne, Isabelle (12 Aug 2005). “Carbon monoxide poisoning in pregnancy”. British Journal of Obstetrics and Gynaecology. 107 (7): 833–8. doi:10.1111/j.1471-0528.2000.tb11078.x. PMC 2146365 . PMID 10901551. Retrieved 7 December 2014. 
  • ^ Griesbauer, Laura. “Methylmercury Contamination in Fish and Shellfish”. CSA. CSA 2007. Retrieved 7 December 2014. 
  • ^ Rushton, Lesley (2003). “Health hazards and waste management”. British Medical Bulletin. 68 (1): 183–97. doi:10.1093/bmb/ldg034. PMID 14757717. 
  • ^ Bullard, Robert. “Environmental Justice for All”. National Humanities Center. Retrieved 9 December 2014. 
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  • ^ a b Raats, Monique (1998). Changing Preconceptions. London: Health Education Authority. p. 11. ISBN 0-7521-1231-7. 
  • ^ Anderson, Lucy M.; Riffle, Lisa; Wilson, Ralph; Travlos, Gregory S.; Lubomirski, Mariusz S.; Alvord, W. Gregory (March 2006). “Preconceptional fasting of fathers alters serum glucose in offspring of mice”. Nutrition. 22 (3): 327–331. doi:10.1016/j.nut.2005.09.006. PMID 16500559. 
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  • ^ a b c de Graaf, Johanna P.; Steegers, Eric A.P.; Bonsel, Gouke J. (April 2013). “Inequalities in perinatal and maternal health”. Current Opinion in Obstetrics and Gynecology. 25 (2): 98–108. doi:10.1097/GCO.0b013e32835ec9b0. PMID 23425665. 
  • ^ a b c d Vos, Amber A.; Posthumus, Anke G.; Bonsel, Gouke J.; Steegers, Eric A.P.; Denktaş, Semiha (August 2014). “Deprived neighborhoods and adverse perinatal outcome: a systematic review and meta-analysis”. Acta Obstetricia et Gynecologica Scandinavica. 93 (8): 727–740. doi:10.1111/aogs.12430. PMID 24834960. 
  • ^ a b c Bradley, Robert H.; Corwyn, Robert F. (February 2002). “S S C D”. Annual Review of Psychology. 53 (1): 371–399. doi:10.1146/annurev.psych.53.100901.135233. PMID 11752490. 
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  • ^ Heath, Clark W. (1992). “The Children of Atomic Bomb Survivors: A Genetic Study”. JAMA: The Journal of the American Medical Association. 268 (5): 661. doi:10.1001/jama.1992.03490050109039. PMC 1682172 . No differences were found (in frequencies of birth defects, stillbirths, etc), thus allaying the immediate public concern that atomic radiation might spawn an epidemic of malformed children 
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  • ^ Winther, J F; Boice, J D; Thomsen, B L; Schull, W J; Stovall, M; j h Olsen (2003). “Sex ratio among offspring of childhood cancer survivors treated with radiotherapy”. British Journal of Cancer. 88 (3): 382–7. doi:10.1038/sj.bjc.6600748. PMC 2747537 . PMID 12569380. 
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  • ^ “NUCLEAR CRISIS: Hiroshima and Nagasaki cast long shadows over radiation science”. www.eenews.net. 11 April 2011. Retrieved 28 October 2014. 
  • ^ Dubrova, Yuri E.; Nesterov, Valeri N.; Krouchinsky, Nicolay G.; Ostapenko, Valdislav A.; Neumann, Rita; Neil, David L.; Jeffreys, Alec J. (25 April 1996). “Human minisatellite mutation rate after the Chernobyl accident”. Nature. 380 (6576): 683–686. Bibcode:1996Natur.380..683D. doi:10.1038/380683a0. PMID 8614461. 
  • ^ Bennett, Burton; Repacholi, Michael; Carr, Zhanat, eds. (2006). Health Effects of the Chernobyl Accident and Special Health Care Programmes: Report of the UN Chernobyl Forum, Expert Group “Health” (PDF). Geneva: World Health Organization (WHO). p. 79. ISBN 978-92-4-159417-2. Retrieved 20 August 2011 
  • ^ Furitsu Katsumi (2005). “Microsatellite mutations show no increases in the children of the Chernobyl liquidators”. Mutation Research/Genetic Toxicology and Environmental Mutagenesis. 581: 69–82. doi:10.1016/j.mrgentox.2004.11.002. 
  • ^ Dickinson HO, Parker L (1999). “Quantifying the effect of population mixing on childhood leukaemia risk: the Seascale cluster” (PDF). British Journal of Cancer. 81 (1): 144–151 [146, 149]. doi:10.1038/sj.bjc.6690664. 
  • ^ Lean, Samantha C.; Derricott, Hayley; Jones, Rebecca L.; Heazell, Alexander E. P. (2017-10-17). “Advanced maternal age and adverse pregnancy outcomes: A systematic review and meta-analysis”. PLOS ONE. 12 (10): e0186287. doi:10.1371/journal.pone.0186287. ISSN 1932-6203. 
  • ^ a b Olshan, Andrew F.; Schnitzer, Patricia G.; Baird, Patricia A. (July 1994). “Paternal age and the risk of congenital heart defects”. Teratology. 50 (1): 80–84. doi:10.1002/tera.1420500111. PMID 7974258. 
  • ^ Yang, Q.; Wen, S.W.; Leader, A.; Chen, X.K.; Lipson, J.; Walker, M. (7 December 2006). “Paternal age and birth defects: how strong is the association?”. Human Reproduction. 22 (3): 696–701. doi:10.1093/humrep/del453. PMID 17164268. 
  • ^ Wiener-Megnazi, Zofnat; Auslender, Ron; Dirnfeld, Martha (12 December 2011). “Advanced paternal age and reproductive outcome”. Asian Journal of Andrology. 14 (1): 69–76. doi:10.1038/aja.2011.69. PMC 3735149 . PMID 22157982. 
  • ^ Bezerra Guimarães MJ, Marques NM, Melo Filho DA (2000). “[Infant mortality rate and social disparity at Recife, the metropolis of the North-East of Brazil]”. Sante (in French). 10 (2): 117–21. PMID 10960809. 
  • ^ Kumar, Abbas and Fausto, eds., Robbins and Cotran’s Pathologic Basis of Disease, 7th edition, p.473.
  • ^ Simonsen, H (25 November 2002). “[Screening of newborns for inborn errors of metabolism by tandem mass spectrometry]”. Ugeskrift for laeger. 164 (48): 5607–12. PMID 12523003. 
  • ^ a b c Wilcken, B; Wiley, V (February 2008). “Newborn screening”. Pathology. 40 (2): 104–15. doi:10.1080/00313020701813743. PMID 18203033. 
  • ^ Ezgu, F (2016). “Inborn Errors of Metabolism”. Advances in clinical chemistry. 73: 195–250. doi:10.1016/bs.acc.2015.12.001. PMID 26975974. 
  • ^ “Newborn screening for DMD shows promise as an international model”. Nationwide Children’s Hospital. 2012-03-19. Retrieved 2018-04-02. 
  • ^ “WHO Disease and injury country estimates”. World Health Organization. 2009. Retrieved Nov 11, 2009. 
  • ^ Gittelsohn, A; Milham, S (1964). “Statistical Study of Twins—Methods”. American Journal of Public Health and the Nations Health. 54 (2): 286–294. doi:10.2105/ajph.54.2.286. PMC 1254713 . PMID 14115496. 
  • ^ Fernando, J; Arena, P; Smith, D. W. (1978). “Sex liability to single structural defects”. American Journal of Diseases of Children. 132 (10): 970–972. PMID 717306. 
  • ^ Lubinsky, M. S. (1997). “Classifying sex biased congenital anomalies”. American Journal of Medical Genetics. 69 (3): 225–228. doi:10.1002/(SICI)1096-8628(19970331)69:3<225::AID-AJMG1>3.0.CO;2-K. PMID 9096746. 
  • ^ Lary, J. M.; Paulozzi, L. J. (2001). “Sex differences in the prevalence of human birth defects: A population-based study”. Teratology. 64 (5): 237–251. doi:10.1002/tera.1070. PMID 11745830. 
  • ^ a b c d e f Cui, W; Ma, C. X.; Tang, Y; Chang, V; Rao, P. V.; Ariet, M; Resnick, M. B.; Roth, J (2005). “Sex differences in birth defects: A study of opposite-sex twins”. Birth Defects Research Part A: Clinical and Molecular Teratology. 73 (11): 876–880. doi:10.1002/bdra.20196. PMID 16265641. 
  • ^ a b World Health Organization reports). “Congenital malformations”, Geneve, 1966, p. 128.
  • ^ Darwin C. (1871) The descent of man and selection in relation to sex. London, John Murray, 1st ed.
  • ^ Kumar, Abbas and Fausto, eds., Robbins and Cotran’s Pathologic Basis of Disease, 7th edition, p.470.
  • ^ Dicke JM (1989). “Teratology: principles and practice”. Med. Clin. North Am. 73 (3): 567–82. PMID 2468064. 
  • ^ a b c d e f g h i j k l m n o p q r Rajewski P. M., Sherman A. L. (1976) The importance of gender in the epidemiology of malignant tumors (systemic-evolutionary approach). In: Mathematical treatment of medical-biological information. M., Nauka, p. 170–181.
  • ^ a b c d Montagu A. (1968) Natural Superiority of Women, The, Altamira Press, 1999.
  • ^ a b c d e f g h i Riley M., Halliday J. (2002) Birth Defects in Victoria 1999–2000, Melbourne.
  • ^ Shaw, G. M.; Carmichael, S. L.; Kaidarova, Z; Harris, J. A. (2003). “Differential risks to males and females for congenital malformations among 2.5 million California births, 1989–1997”. Birth Defects Research Part A: Clinical and Molecular Teratology. 67 (12): 953–958. doi:10.1002/bdra.10129. PMID 14745913. 
  • ^ Reyes, F. I.; Boroditsky, R. S.; Winter, J. S.; Faiman, C (1974). “Studies on human sexual development. II. Fetal and maternal serum gonadotropin and sex steroid concentrations”. The Journal of Clinical Endocrinology & Metabolism. 38 (4): 612–617. doi:10.1210/jcem-38-4-612. PMID 4856555. 
  • ^ “Key Findings: Updated National Birth Prevalence Estimates for Selected Birth Defects in the United States, 2004–2006”. CDC. Centers for Disease Control and Prevention (CDC) and the National Birth Defects Prevention Network. Retrieved October 1, 2014. 
  • External links[edit]

    • CDC’s National Center on Birth Defects and Developmental Disabilities

    X/Y linked

    Translocations

    Other

    • Ewing’s sarcoma t(11 FLI1; 22 EWS)
    • Synovial sarcoma t(x SYT;18 SSX)
    • Dermatofibrosarcoma protuberans t(17 COL1A1;22 PDGFB)
    • Myxoid liposarcoma t(12 DDIT3; 16 FUS)
    • Desmoplastic small-round-cell tumor t(11 WT1; 22 EWS)
    • Alveolar rhabdomyosarcoma t(2 PAX3; 13 FOXO1) t (1 PAX7; 13 FOXO1)

    Other

    • Fragile X syndrome
    • Uniparental disomy
    • XX male syndrome/46,XX testicular disorders of sex development
    • Marker chromosome
    • Ring chromosome
      • 6; 9; 14; 15; 18; 20; 21, 22


    Contraception

    For other uses, see Birth control (disambiguation).

    Birth control, also known as contraception and fertility control, is a method or device used to prevent pregnancy.[1] Birth control has been used since ancient times, but effective and safe methods of birth control only became available in the 20th century.[2] Planning, making available, and using birth control is called family planning.[3][4] Some cultures limit or discourage access to birth control because they consider it to be morally, religiously, or politically undesirable.[2]

    The most effective methods of birth control are sterilization by means of vasectomy in males and tubal ligation in females, intrauterine devices (IUDs), and implantable birth control.[5] This is followed by a number of hormone-based methods including oral pills, patches, vaginal rings, and injections.[5] Less effective methods include physical barriers such as condoms, diaphragms and birth control sponges and fertility awareness methods.[5] The least effective methods are spermicides and withdrawal by the male before ejaculation.[5] Sterilization, while highly effective, is not usually reversible; all other methods are reversible, most immediately upon stopping them.[5] Safe sex practices, such as with the use of male or female condoms, can also help prevent sexually transmitted infections.[6] Other methods of birth control do not protect against sexually transmitted diseases.[7] Emergency birth control can prevent pregnancy if taken within the 72 to 120 hours after unprotected sex.[8][9] Some argue not having sex as a form of birth control, but abstinence-only sex education may increase teenage pregnancies if offered without birth control education, due to non-compliance.[10][11]

    In teenagers, pregnancies are at greater risk of poor outcomes.[12] Comprehensive sex education and access to birth control decreases the rate of unwanted pregnancies in this age group.[12][13] While all forms of birth control can generally be used by young people,[14] long-acting reversible birth control such as implants, IUDs, or vaginal rings are more successful in reducing rates of teenage pregnancy.[13] After the delivery of a child, a woman who is not exclusively breastfeeding may become pregnant again after as few as four to six weeks.[14] Some methods of birth control can be started immediately following the birth, while others require a delay of up to six months.[14] In women who are breastfeeding, progestin-only methods are preferred over combined oral birth control pills.[14] In women who have reached menopause, it is recommended that birth control be continued for one year after the last period.[14]

    About 222 million women who want to avoid pregnancy in developing countries are not using a modern birth control method.[15][16] Birth control use in developing countries has decreased the number of deaths during or around the time of pregnancy by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% if the full demand for birth control were met.[17][18] By lengthening the time between pregnancies, birth control can improve adult women’s delivery outcomes and the survival of their children.[17] In the developing world women’s earnings, assets, weight, and their children’s schooling and health all improve with greater access to birth control.[19] Birth control increases economic growth because of fewer dependent children, more women participating in the workforce, and less use of scarce resources.[19][20]

    Play media

    Video explaining how to prevent unwanted pregnancy

    Contents

    • 1 Methods
      • 1.1 Hormonal
      • 1.2 Barrier
      • 1.3 Intrauterine devices
      • 1.4 Sterilization
      • 1.5 Behavioral
        • 1.5.1 Fertility awareness
        • 1.5.2 Withdrawal
        • 1.5.3 Abstinence
        • 1.5.4 Lactation
      • 1.6 Emergency
      • 1.7 Dual protection
    • 2 Effects
      • 2.1 Health
      • 2.2 Finances
    • 3 Prevalence
    • 4 History
      • 4.1 Early history
      • 4.2 Birth control movement
      • 4.3 Modern methods
    • 5 Society and culture
      • 5.1 Legal positions
      • 5.2 Religious views
      • 5.3 World Contraception Day
      • 5.4 Misconceptions
    • 6 Research directions
      • 6.1 Females
      • 6.2 Males
    • 7 Other animals
    • 8 References
    • 9 Further reading
    • 10 External links

    Methods[edit]

    See also: Comparison of birth control methods

    Birth control methods include barrier methods, hormonal birth control, intrauterine devices (IUDs), sterilization, and behavioral methods. They are used before or during sex while emergency contraceptives are effective for up to five days after sex. Effectiveness is generally expressed as the percentage of women who become pregnant using a given method during the first year,[25] and sometimes as a lifetime failure rate among methods with high effectiveness, such as tubal ligation.[26]

    The most effective methods are those that are long acting and do not require ongoing health care visits.[27] Surgical sterilization, implantable hormones, and intrauterine devices all have first-year failure rates of less than 1%.[21] Hormonal contraceptive pills, patches or vaginal rings, and the lactational amenorrhea method (LAM), if adhered to strictly, can also have first-year (or for LAM, first-6-month) failure rates of less than 1%.[27] With typical use, first-year failure rates are considerably high, at 9%, due to inconsistent use.[21] Other methods such as condoms, diaphragms, and spermicides have higher first-year failure rates even with perfect usage.[27] The American Academy of Pediatrics recommends long acting reversible birth control as first line for young individuals.[28]

    While all methods of birth control have some potential adverse effects, the risk is less than that of pregnancy.[27] After stopping or removing many methods of birth control, including oral contraceptives, IUDs, implants and injections, the rate of pregnancy during the subsequent year is the same as for those who used no birth control.[29]

    For individuals with specific health problems, certain forms of birth control may require further investigations.[30] For women who are otherwise healthy, many methods of birth control should not require a medical exam—including birth control pills, injectable or implantable birth control, and condoms.[31] For example, a pelvic exam, breast exam, or blood test before starting birth control pills does not appear to affect outcomes.[32][33] In 2009, the World Health Organization (WHO) published a detailed list of medical eligibility criteria for each type of birth control.[30]

    Hormonal[edit]

    Hormonal contraception is available in a number of different forms, including oral pills, implants under the skin, injections, patches, IUDs and a vaginal ring. They are currently available only for women, although hormonal contraceptives for men have been and are being clinically tested.[34] There are two types of oral birth control pills, the combined oral contraceptive pills (which contain both estrogen and a progestin) and the progestogen-only pills (sometimes called minipills).[35] If either is taken during pregnancy, they do not increase the risk of miscarriage nor cause birth defects.[33] Both types of birth control pills prevent fertilization mainly by inhibiting ovulation and thickening cervical mucus.[36][37] They may also change the lining of the uterus and thus decrease implantation.[37] Their effectiveness depends on the user’s adherence to taking the pills.[33]

    Combined hormonal contraceptives are associated with a slightly increased risk of venous and arterial blood clots.[38] Venous clots, on average, increase from 2.8 to 9.8 per 10,000 women years[39] which is still less than that associated with pregnancy.[38] Due to this risk, they are not recommended in women over 35 years of age who continue to smoke.[40] Due to the increased risk, they are included in decision tools such as the DASH score and PERC rule used to predict the risk of blood clots.[41]

    The effect on sexual desire is varied, with increase or decrease in some but with no effect in most.[42] Combined oral contraceptives reduce the risk of ovarian cancer and endometrial cancer and do not change the risk of breast cancer.[43][44] They often reduce menstrual bleeding and painful menstruation cramps.[33] The lower doses of estrogen released from the vaginal ring may reduce the risk of breast tenderness, nausea, and headache associated with higher dose estrogen products.[43]

    Progestin-only pills, injections and intrauterine devices are not associated with an increased risk of blood clots and may be used by women with a history of blood clots in their veins.[38][45] In those with a history of arterial blood clots, non-hormonal birth control or a progestin-only method other than the injectable version should be used.[38] Progestin-only pills may improve menstrual symptoms and can be used by breastfeeding women as they do not affect milk production. Irregular bleeding may occur with progestin-only methods, with some users reporting no periods.[46] The progestins drospirenone and desogestrel minimize the androgenic side effects but increase the risks of blood clots and are thus not first line.[47] The perfect use first-year failure rate of injectable progestin is 0.2%; the typical use first failure rate is 6%.[21]

    • Three varieties of birth control pills in calendar oriented packaging

    • Birth control pills

    • A transdermal contraceptive patch

    • A NuvaRing vaginal ring

    Barrier[edit]

    Barrier contraceptives are devices that attempt to prevent pregnancy by physically preventing sperm from entering the uterus.[48] They include male condoms, female condoms, cervical caps, diaphragms, and contraceptive sponges with spermicide.[48]

    Globally, condoms are the most common method of birth control.[49] Male condoms are put on a man’s erect penis and physically block ejaculated sperm from entering the body of a sexual partner.[50] Modern condoms are most often made from latex, but some are made from other materials such as polyurethane, or lamb’s intestine.[50] Female condoms are also available, most often made of nitrile, latex or polyurethane.[51] Male condoms have the advantage of being inexpensive, easy to use, and have few adverse effects.[52] Making condoms available to teenagers does not appear to affect the age of onset of sexual activity or its frequency.[53] In Japan, about 80% of couples who are using birth control use condoms, while in Germany this number is about 25%,[54] and in the United States it is 18%.[55]

    Male condoms and the diaphragm with spermicide have typical use first-year failure rates of 18% and 12%, respectively.[21] With perfect use condoms are more effective with a 2% first-year failure rate versus a 6% first-year rate with the diaphragm.[21] Condoms have the additional benefit of helping to prevent the spread of some sexually transmitted infections such as HIV/AIDS, however, condoms made from animal intestine do not.[5][56]

    Contraceptive sponges combine a barrier with a spermicide.[27] Like diaphragms, they are inserted vaginally before intercourse and must be placed over the cervix to be effective.[27] Typical failure rates during the first year depend on whether or not a woman has previously given birth, being 24% in those who have and 12% in those who have not.[21] The sponge can be inserted up to 24 hours before intercourse and must be left in place for at least six hours afterward.[27] Allergic reactions[57] and more severe adverse effects such as toxic shock syndrome have been reported.[58]

    • A rolled up male condom.

    • An unrolled male latex condom

    • A polyurethane female condom

    • A diaphragm vaginal-cervical barrier, in its case with a quarter U.S. coin.

    • A contraceptive sponge set inside its open package.

    Intrauterine devices[edit]

    Copper T shaped IUD with removal strings

    The current intrauterine devices (IUD) are small devices, often ‘T’-shaped, containing either copper or levonorgestrel, which are inserted into the uterus. They are one form of long-acting reversible contraception which are the most effective types of reversible birth control.[59] Failure rates with the copper IUD is about 0.8% while the levonorgestrel IUD has a failure rates of 0.2% in the first year of use.[60] Among types of birth control, they, along with birth control implants, result in the greatest satisfaction among users.[61] As of 2007, IUDs are the most widely used form of reversible contraception, with more than 180 million users worldwide.[62]

    Evidence supports effectiveness and safety in adolescents[61] and those who have and have not previously had children.[63] IUDs do not affect breastfeeding and can be inserted immediately after delivery.[64] They may also be used immediately after an abortion.[65] Once removed, even after long term use, fertility returns to normal immediately.[66]

    While copper IUDs may increase menstrual bleeding and result in more painful cramps,[67] hormonal IUDs may reduce menstrual bleeding or stop menstruation altogether.[64] Cramping can be treated with painkillers like non-steroidal anti-inflammatory drugs.[68] Other potential complications include expulsion (2–5%) and rarely perforation of the uterus (less than 0.7%).[64][68] A previous model of the intrauterine device (the Dalkon shield) was associated with an increased risk of pelvic inflammatory disease, however the risk is not affected with current models in those without sexually transmitted infections around the time of insertion.[69]

    Sterilization[edit]

    Surgical sterilization is available in the form of tubal ligation for women and vasectomy for men.[2] There are no significant long term side effects, and tubal ligation decreases the risk of ovarian cancer.[2] Short term complications are twenty times less likely from a vasectomy than a tubal ligation.[2][70] After a vasectomy, there may be swelling and pain of the scrotum which usually resolves in one or two weeks.[71] With tubal ligation, complications occur in 1 to 2 percent of procedures with serious complications usually due to the anesthesia.[72] Neither method offers protection from sexually transmitted infections.[2]

    This decision may cause regret in some men and women. Of women aged over 30 who have undergone tubal ligation, about 5% regret their decision, as compared with 20% of women aged under 30.[2] By contrast, less than 5% of men are likely to regret sterilization. Men who are more likely to regret sterilization are younger, have young or no children, or have an unstable marriage.[73] In a survey of biological parents, 9% stated they would not have had children if they were able to do it over again.[74]

    Although sterilization is considered a permanent procedure,[75] it is possible to attempt a tubal reversal to reconnect the fallopian tubes or a vasectomy reversal to reconnect the vasa deferentia. In women, the desire for a reversal is often associated with a change in spouse.[75] Pregnancy success rates after tubal reversal are between 31 and 88 percent, with complications including an increased risk of ectopic pregnancy.[75] The number of males who request reversal is between 2 and 6 percent.[76] Rates of success in fathering another child after reversal are between 38 and 84 percent; with success being lower the longer the time period between the vasectomy and the reversal.[76] Sperm extraction followed by in vitro fertilization may also be an option in men.[77]

    Behavioral[edit]

    Behavioral methods involve regulating the timing or method of intercourse to prevent introduction of sperm into the female reproductive tract, either altogether or when an egg may be present.[78] If used perfectly the first-year failure rate may be around 3.4%, however if used poorly first-year failure rates may approach 85%.[79]

    Fertility awareness[edit]

    A CycleBeads tool, used for estimating fertility based on days since last menstruation

    Fertility awareness methods involve determining the most fertile days of the menstrual cycle and avoiding unprotected intercourse.[78] Techniques for determining fertility include monitoring basal body temperature, cervical secretions, or the day of the cycle.[78] They have typical first-year failure rates of 24%; perfect use first-year failure rates depend on which method is used and range from 0.4% to 5%.[21] The evidence on which these estimates are based, however, is poor as the majority of people in trials stop their use early.[78] Globally, they are used by about 3.6% of couples.[80] If based on both basal body temperature and another primary sign, the method is referred to as symptothermal. First-year failure rates of 20% overall and 0.4% for perfect use have been reported in clinical studies of the symptothermal method.[81][21] A number of fertility tracking apps are available, as of 2016, but they are more commonly designed to assist those trying to get pregnant rather than prevent pregnancy.[82]

    Withdrawal[edit]

    The withdrawal method (also known as coitus interruptus) is the practice of ending intercourse (“pulling out”) before ejaculation.[83] The main risk of the withdrawal method is that the man may not perform the maneuver correctly or in a timely manner.[83] First-year failure rates vary from 4% with perfect usage to 22% with typical usage.[21] It is not considered birth control by some medical professionals.[27]

    There is little data regarding the sperm content of pre-ejaculatory fluid.[84] While some tentative research did not find sperm,[84] one trial found sperm present in 10 out of 27 volunteers.[85] The withdrawal method is used as birth control by about 3% of couples.[80]

    Abstinence[edit]

    Sexual abstinence may be used as a form of birth control, meaning either not engaging in any type of sexual activity, or specifically not engaging in vaginal intercourse, while engaging in other forms of non-vaginal sex.[86][87] Complete sexual abstinence is 100% effective in preventing pregnancy.[88][89] However, among those who take a pledge to abstain from premarital sex, as many as 88% who engage in sex, do so prior to marriage.[90] The choice to abstain from sex cannot protect against pregnancy as a result of rape, and public health efforts emphasizing abstinence to reduce unwanted pregnancy may have limited effectiveness, especially in developing countries and among disadvantaged groups.[91][92]

    Deliberate non-penetrative sex without vaginal sex or deliberate oral sex without vaginal sex are also sometimes considered birth control.[86] While this generally avoids pregnancy, pregnancy can still occur with intercrural sex and other forms of penis-near-vagina sex (genital rubbing, and the penis exiting from anal intercourse) where sperm can be deposited near the entrance to the vagina and can travel along the vagina’s lubricating fluids.[93][94]

    Abstinence-only sex education does not reduce teenage pregnancy.[7][95] Teen pregnancy rates and STI rates are generally the same or higher in states where students are given abstinence-only education, as compared with comprehensive sex education.[95] Some authorities recommend that those using abstinence as a primary method have backup methods available (such as condoms or emergency contraceptive pills).[96]

    Lactation[edit]

    The lactational amenorrhea method involves the use of a woman’s natural postpartum infertility which occurs after delivery and may be extended by breastfeeding.[97] This usually requires the presence of no periods, exclusively breastfeeding the infant, and a child younger than six months.[24] The World Health Organization states that if breastfeeding is the infant’s only source of nutrition, the failure rate is 2% in the six months following delivery.[98] Six uncontrolled studies of lactational amenorrhea method users found failure rates at 6 months postpartum between 0% and 7.5%.[99][needs update] Failure rates increase to 4–7% at one year and 13% at two years.[100] Feeding formula, pumping instead of nursing, the use of a pacifier, and feeding solids all increase its failure rate.[101] In those who are exclusively breastfeeding, about 10% begin having periods before three months and 20% before six months.[100] In those who are not breastfeeding, fertility may return four weeks after delivery.[100]

    Emergency[edit]

    A split dose of two emergency contraceptive pills

    Emergency contraceptive methods are medications (sometimes misleadingly referred to as “morning-after pills”)[102] or devices used after unprotected sexual intercourse with the hope of preventing pregnancy.[8] They work primarily by preventing ovulation or fertilization.[2][103] They are unlikely to affect implantation, but this has not been completely excluded.[103] A number of options exist, including high dose birth control pills, levonorgestrel, mifepristone, ulipristal and IUDs.[104] Levonorgestrel pills, when used within 3 days, decrease the chance of pregnancy after a single episode of unprotected sex or condom failure by 70% (resulting in a pregnancy rate of 2.2%).[8] Ulipristal, when used within 5 days, decreases the chance of pregnancy by about 85% (pregnancy rate 1.4%) and might be a little more effective than levonorgestrel.[8][104][105] Mifepristone is also more effective than levonorgestrel, while copper IUDs are the most effective method.[104] IUDs can be inserted up to five days after intercourse and prevent about 99% of pregnancies after an episode of unprotected sex (pregnancy rate of 0.1 to 0.2%).[2][106] This makes them the most effective form of emergency contraceptive.[107] In those who are overweight or obese, levonorgestrel is less effective and an IUD or ulipristal is recommended.[108]

    Providing emergency contraceptive pills to women in advance does not affect rates of sexually transmitted infections, condom use, pregnancy rates, or sexual risk-taking behavior.[109][110] All methods have minimal side effects.[104]

    Dual protection[edit]

    Dual protection is the use of methods that prevent both sexually transmitted infections and pregnancy.[111] This can be with condoms either alone or along with another birth control method or by the avoidance of penetrative sex.[112][113]

    If pregnancy is a high concern, using two methods at the same time is reasonable.[112] For example, two forms of birth control are recommended in those taking the anti-acne drug isotretinoin or anti-epileptic drugs like carbamazepine, due to the high risk of birth defects if taken during pregnancy.[114][115]

    Effects[edit]

    Health[edit]

    See also: Maternal health

    Maternal mortality rate as of 2010.[116]

    Contraceptive use and total fertility rate by region.

    Contraceptive use in developing countries is estimated to have decreased the number of maternal deaths by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% of deaths if the full demand for birth control were met.[17][18] These benefits are achieved by reducing the number of unplanned pregnancies that subsequently result in unsafe abortions and by preventing pregnancies in those at high risk.[17]

    Birth control also improves child survival in the developing world by lengthening the time between pregnancies.[17] In this population, outcomes are worse when a mother gets pregnant within eighteen months of a previous delivery.[17][117] Delaying another pregnancy after a miscarriage however does not appear to alter risk and women are advised to attempt pregnancy in this situation whenever they are ready.[117]

    Teenage pregnancies, especially among younger teens, are at greater risk of adverse outcomes including early birth, low birth weight, and death of the infant.[12] In the United States 82% of pregnancies in those between 15 and 19 are unplanned.[68] Comprehensive sex education and access to birth control are effective in decreasing pregnancy rates in this age group.[118]

    Finances[edit]

    See also: Family economics and Cost of raising a child

    Countries by fertility rate as of 2015

    In the developing world, birth control increases economic growth due to there being fewer dependent children and thus more women participating in or increased contribution to the workforce.[19] Women’s earnings, assets, body mass index, and their children’s schooling and body mass index all improve with greater access to birth control.[19] Family planning, via the use of modern birth control, is one of the most cost-effective health interventions.[119] For every dollar spent, the United Nations estimates that two to six dollars are saved.[16] These cost savings are related to preventing unplanned pregnancies and decreasing the spread of sexually transmitted illnesses.[119] While all methods are beneficial financially, the use of copper IUDs resulted in the greatest savings.[119]

    The total medical cost for a pregnancy, delivery and care of a newborn in the United States is on average $21,000 for a vaginal delivery and $31,000 for a caesarean delivery as of 2012.[120] In most other countries, the cost is less than half.[120] For a child born in 2011, an average US family will spend $235,000 over 17 years to raise them.[121]

    Prevalence[edit]

    Main article: Prevalence of birth control

    World map colored according to modern birth control use. Each shading level represents a range of six percentage points, with usage less than or equal to:

    Globally, as of 2009, approximately 60% of those who are married and able to have children use birth control.[122] How frequently different methods are used varies widely between countries.[122] The most common method in the developed world is condoms and oral contraceptives, while in Africa it is oral contraceptives and in Latin America and Asia it is sterilization.[122] In the developing world overall, 35% of birth control is via female sterilization, 30% is via IUDs, 12% is via oral contraceptives, 11% is via condoms, and 4% is via male sterilization.[122]

    While less used in the developed countries than the developing world, the number of women using IUDs as of 2007 was more than 180 million.[62] Avoiding sex when fertile is used by about 3.6% of women of childbearing age, with usage as high as 20% in areas of South America.[123] As of 2005, 12% of couples are using a male form of birth control (either condoms or a vasectomy) with higher rates in the developed world.[124] Usage of male forms of birth control has decreased between 1985 and 2009.[122] Contraceptive use among women in Sub-Saharan Africa has risen from about 5% in 1991 to about 30% in 2006.[125]

    As of 2012, 57% of women of childbearing age want to avoid pregnancy (867 of 1,520 million).[126] About 222 million women however were not able to access birth control, 53 million of whom were in sub-Saharan Africa and 97 million of whom were in Asia.[126] This results in 54 million unplanned pregnancies and nearly 80,000 maternal deaths a year.[122] Part of the reason that many women are without birth control is that many countries limit access due to religious or political reasons,[2] while another contributor is poverty.[127] Due to restrictive abortion laws in Sub-Saharan Africa, many women turn to unlicensed abortion providers for unintended pregnancy, resulting in about 2–4% obtaining unsafe abortions each year.[127]

    History[edit]

    Main article: History of birth control

    Early history[edit]

    Ancient silver coin from Cyrene depicting a stalk of silphium

    The Egyptian Ebers Papyrus from 1550 BC and the Kahun Papyrus from 1850 BC have within them some of the earliest documented descriptions of birth control: the use of honey, acacia leaves and lint to be placed in the vagina to block sperm.[128][129] It is believed that in Ancient Greece silphium was used as birth control which, due to its effectiveness and thus desirability, was harvested into extinction.[130]

    In medieval Europe, any effort to halt pregnancy was deemed immoral by the Catholic Church,[128] although it is believed that women of the time still used a number of birth control measures, such as coitus interruptus and inserting lily root and rue into the vagina.[131] Women in the Middle Ages were also encouraged to tie weasel testicles around their thighs during sex to prevent pregnancy.[132] The oldest condoms discovered to date were recovered in the ruins of Dudley Castle in England, and are dated back to 1640.[132] They were made of animal gut, and were most likely used to prevent the spread of sexually transmitted diseases during the English Civil War.[132] Casanova, living in 18th century Italy, described the use of a lambskin covering to prevent pregnancy; however, condoms only became widely available in the 20th century.[128]

    Birth control movement[edit]

    “And the villain still pursues her”, a satirical Victorian era postcard

    The birth control movement developed during the 19th and early 20th centuries.[133] The Malthusian League, based on the ideas of Thomas Malthus, was established in 1877 in the United Kingdom to educate the public about the importance of family planning and to advocate for getting rid of penalties for promoting birth control.[134] It was founded during the “Knowlton trial” of Annie Besant and Charles Bradlaugh, who were prosecuted for publishing on various methods of birth control.[135]

    In the United States, Margaret Sanger and Otto Bobsein popularized the phrase “birth control” in 1914.[136][137] Sanger primarily advocated for birth control on the idea that it would prevent women from seeking unsafe abortions, but during her lifetime, she began to campaign for it on the grounds that it would reduce mental and physical defects.[138][139] She was mainly active in the United States but had gained an international reputation by the 1930s. At the time, under the Comstock Law, distribution of birth control information was illegal. She jumped bail in 1914 after her arrest for distributing birth control information and left the United States for the United Kingdom.[140] In the U.K., Sanger, influenced by Havelock Ellis, further developed her arguments for birth control. She believed women needed to enjoy sex without fearing a pregnancy. During her time abroad, Sanger also saw a more flexible diaphragm in a Dutch clinic, which she thought was a better form of contraceptive.[139] Once Sanger returned to the United States, she established a short-lived birth-control clinic with the help of her sister, Ethel Bryne, based in the Brownville section of Brooklyn, New York[141] in 1916. It was shut down after eleven days and resulted in her arrest.[142] The publicity surrounding the arrest, trial, and appeal sparked birth control activism across the United States.[143] Besides her sister, Sanger was helped in the movement by her first husband, William Sanger, who distributed copies of “Family Limitation.” Sanger’s second husband, James Noah H. Slee, would also later become involved in the movement, acting as its main funder.[139]

    The first permanent birth-control clinic was established in Britain in 1921 by Marie Stopes working with the Malthusian League.[144] The clinic, run by midwives and supported by visiting doctors,[145] offered women’s birth-control advice and taught them the use of a cervical cap. Her clinic made contraception acceptable during the 1920s by presenting it in scientific terms. In 1921, Sanger founded the American Birth Control League, which later became the Planned Parenthood Federation of America.[146] In 1924 the Society for the Provision of Birth Control Clinics was founded to campaign for municipal clinics; this led to the opening of a second clinic in Greengate, Salford in 1926.[147] Throughout the 1920s, Stopes and other feminist pioneers, including Dora Russell and Stella Browne, played a major role in breaking down taboos about sex. In April 1930 the Birth Control Conference assembled 700 delegates and was successful in bringing birth control and abortion into the political sphere – three months later, the Ministry of Health, in the United Kingdom, allowed local authorities to give birth-control advice in welfare centres.[148]

    In 1936 the U.S. court ruled in U.S. v. One Package that medically prescribing contraception to save a person’s life or well-being was not illegal under the Comstock Law; following this decision, the American Medical Association Committee on Contraception revoked its 1936 statement condemning birth control. A national survey in 1937 showed 71 percent of the adult population supported the use of contraception. By 1938 347 birth control clinics were running in the United States despite their advertisement still being illegal. First Lady Eleanor Roosevelt publicly supported birth control and family planning.[149] In 1966, President Lyndon B. Johnson started endorsing public funding for family planning services, and the Federal Government began subsidizing birth control services for low-income families.[150] The Affordable Care Act, passed into law on March 23, 2010 under President Barack Obama, requires all plans in the Health Insurance Marketplace to cover contraceptive methods. These include barrier methods, hormonal methods, implanted devices, emergency contraceptives, and sterilization procedures.[151]

    Modern methods[edit]

    In 1909, Richard Richter developed the first intrauterine device made from silkworm gut, which was further developed and marketed in Germany by Ernst Gräfenberg in the late 1920s.[152] In 1951, a chemist, named Carl Djerassi from Mexico City made the hormones in progesterone pills using Mexican yams.[153] Djerassi had chemically created the pill but was not equipped to distribute it to patients. Meanwhile, Gregory Pincus and John Rock with help from the Planned Parenthood Federation of America developed the first birth control pills in the 1950s, such as mestranol/noretynodrel, which became publicly available in the 1960s through the Food and Drug Administration under the name Enovid.[146][154] Medical abortion became an alternative to surgical abortion with the availability of prostaglandin analogs in the 1970s and mifepristone in the 1980s.[155]

    Society and culture[edit]

    Legal positions[edit]

    Further information: Timeline of reproductive rights legislation

    Human rights agreements require most governments to provide family planning and contraceptive information and services. These include the requirement to create a national plan for family planning services, remove laws that limit access to family planning, ensure that a wide variety of safe and effective birth control methods are available including emergency contraceptives, make sure there are appropriately trained healthcare providers and facilities at an affordable price, and create a process to review the programs implemented. If governments fail to do the above it may put them in breach of binding international treaty obligations.[156]

    In the United States, the 1965 Supreme Court decision Griswold v. Connecticut overturned a state law prohibiting dissemination of contraception information based on a constitutional right to privacy for marital relationships. In 1971, Eisenstadt v. Baird extended this right to privacy to single people.[157]

    In 2010, the United Nations launched the Every Woman Every Child movement to assess the progress toward meeting women’s contraceptive needs. The initiative has set a goal of increasing the number of users of modern birth control by 120 million women in the world’s 69 poorest countries by the year 2020. Additionally, they aim to eradicate discrimination against girls and young women who seek contraceptives.[158] The American Congress of Obstetricians and Gynecologists (ACOG) recommended in 2014 that oral birth control pills should be over the counter medications.[159]

    Since at least the 1870s, American religious, medical, legislative, and legal commentators have debated contraception laws. Ana Garner and Angela Michel have found that in these discussions men often attach reproductive rights to moral and political matters, as part of an ongoing attempt to regulate human bodies. In press coverage between 1873–2013 they found a divide between institutional ideology and real-life experiences of women.[160]

    Religious views[edit]

    Main article: Religion and birth control
    See also: Jewish views on contraception

    Religions vary widely in their views of the ethics of birth control.[161] The Roman Catholic Church officially only accepts natural family planning,[162] although large numbers of Catholics in developed countries accept and use modern methods of birth control.[163][164][165] Among Protestants, there is a wide range of views from supporting none, such as in the Quiverfull movement, to allowing all methods of birth control.[166] Views in Judaism range from the stricter Orthodox sect, which prohibits all methods of birth control, to the more relaxed Reform sect, which allows most.[167] Hindus may use both natural and modern contraceptives.[168] A common Buddhist view is that preventing conception is acceptable, while intervening after conception has occurred is not.[169] In Islam, contraceptives are allowed if they do not threaten health, although their use is discouraged by some.[170]

    World Contraception Day[edit]

    September 26 is World Contraception Day, devoted to raising awareness and improving education about sexual and reproductive health, with a vision of a world where every pregnancy is wanted.[171] It is supported by a group of governments and international NGOs, including the Office of Population Affairs, the Asian Pacific Council on Contraception, Centro Latinamericano Salud y Mujer, the European Society of Contraception and Reproductive Health, the German Foundation for World Population, the International Federation of Pediatric and Adolescent Gynecology, International Planned Parenthood Federation, the Marie Stopes International, Population Services International, the Population Council, the United States Agency for International Development (USAID), and Women Deliver.[171]

    Misconceptions[edit]

    There are a number of common misconceptions regarding sex and pregnancy.[172] Douching after sexual intercourse is not an effective form of birth control.[173] Additionally, it is associated with a number of health problems and thus is not recommended.[174] Women can become pregnant the first time they have sexual intercourse[175] and in any sexual position.[176] It is possible, although not very likely, to become pregnant during menstruation.[177]

    Research directions[edit]

    Females[edit]

    Improvements of existing birth control methods are needed, as around half of those who get pregnant unintentionally are using birth control at the time.[27] A number of alterations of existing contraceptive methods are being studied, including a better female condom, an improved diaphragm, a patch containing only progestin, and a vaginal ring containing long-acting progesterone.[178] This vaginal ring appears to be effective for three or four months and is currently available in some areas of the world.[178] For women who rarely have sex, the taking of the hormonal birth control levonorgestrel around the time of sex looks promising.[179]

    A number of methods to perform sterilization via the cervix are being studied. One involves putting quinacrine in the uterus which causes scarring and infertility. While the procedure is inexpensive and does not require surgical skills, there are concerns regarding long-term side effects.[180] Another substance, polidocanol, which functions in the same manner is being looked at.[178] A device called Essure, which expands when placed in the fallopian tubes and blocks them, was approved in the United States in 2002.[180]

    Males[edit]

    Main article: Male contraceptive

    Methods of male birth control include condoms, vasectomies and withdrawal.[181][182] Between 25 and 75% of males who are sexually active would use hormonal birth control if it was available for them.[124][181] A number of hormonal and non-hormonal methods are in trials,[124] and there is some research looking at the possibility of contraceptive vaccines.[183]

    A reversible surgical method under investigation is reversible inhibition of sperm under guidance (RISUG) which consists of injecting a polymer gel, styrene maleic anhydride in dimethyl sulfoxide, into the vas deferens. An injection with sodium bicarbonate washes out the substance and restores fertility. Another is an intravas device which involves putting a urethane plug into the vas deferens to block it. A combination of an androgen and a progestin seems promising, as do selective androgen receptor modulators.[124] Ultrasound and methods to heat the testicles have undergone preliminary studies.[184]

    Other animals[edit]

    Neutering or spaying, which involves removing some of the reproductive organs, is often carried out as a method of birth control in household pets. Many animal shelters require these procedures as part of adoption agreements.[185] In large animals the surgery is known as castration.[186]

    Birth control is also being considered as an alternative to hunting as a means of controlling overpopulation in wild animals.[187] Contraceptive vaccines have been found to be effective in a number of different animal populations.[188][189] Kenyan goat herders fix a skirt, called an olor, to male goats to prevent them from impregnating female goats.[190]

    References[edit]

  • ^ “Definition of Birth control”. MedicineNet. Archived from the original on August 6, 2012. Retrieved August 9, 2012. 
  • ^ a b c d e f g h i j Hanson, S.J.; Burke, Anne E. (December 21, 2010). “Fertility control: contraception, sterilization, and abortion”. In Hurt, K. Joseph; Guile, Matthew W.; Bienstock, Jessica L.; Fox, Harold E.; Wallach, Edward E. The Johns Hopkins manual of gynecology and obstetrics (4th ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. pp. 382–395. ISBN 978-1-60547-433-5. 
  • ^ Oxford English Dictionary. Oxford University Press. June 2012. 
  • ^ World Health Organization (WHO). “Family planning”. Health topics. World Health Organization (WHO). Archived from the original on March 18, 2016. Retrieved March 28, 2016. 
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  • ^ Glasier, A; Cameron, ST; Blithe, D; Scherrer, B; Mathe, H; Levy, D; Gainer, E; Ulmann, A (Oct 2011). “Can we identify women at risk of pregnancy despite using emergency contraception? Data from randomized trials of ulipristal acetate and levonorgestrel”. Contraception. 84 (4): 363–7. doi:10.1016/j.contraception.2011.02.009. PMID 21920190. 
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  • ^ a b “Family Planning Timeline”. Congressional Digest. 2015. 
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  • ^ Hall, Lesley (2011). The life and times of Stella Browne : feminist and free spirit. London: I. B. Tauris. p. 173. ISBN 978-1-84885-583-0. 
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  • ^ “Birth control benefits and reproductive health care options in the Health Insurance Marketplace”. HealthCare.gov. Archived from the original on February 12, 2016. Retrieved February 17, 2016. 
  • ^ Fritz, Marc A.; Speroff, Leon (2011). “Intrauterine contraception”. Clinical gynecologic endocrinology and infertility (8th ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. pp. 1095–1098. ISBN 978-0-7817-7968-5. Archived from the original on November 16, 2016. 
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  • ^ Cottingham J.; Germain A.; Hunt P. (2012). “Use of human rights to meet the unmet need for family planning”. The Lancet. 380 (9837): 172–180. doi:10.1016/S0140-6736(12)60732-6. PMID 22784536. 
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  • ^ Susheela Singh; Jacqueline E. Darroch (June 2012). “Adding It Up: Costs and Benefits of Contraceptive Services Estimates for 2012” (PDF). Guttmacher Institute and United Nations Population Fund (UNFPA), 201. Archived (PDF) from the original on August 5, 2012. 
  • ^ ACOG (September 9, 2014). “ACOG Statement on OTC Access to Contraception”. Archived from the original on September 10, 2014. Retrieved September 11, 2014. 
  • ^ Garner, A. C.; Michel, A. R. (4 November 2016). “”The Birth Control Divide”: U.S. Press Coverage of Contraception, 1873–2013″. Journalism & Communication Monographs. 18 (4): 180–234. doi:10.1177/1522637916672457. 
  • ^ Srikanthan, A; Reid, RL (February 2008). “Religious and cultural influences on contraception”. Journal of Obstetrics and Gynaecology Canada. 30 (2): 129–37. doi:10.1016/s1701-2163(16)32736-0. PMID 18254994. 
  • ^ Pope Paul VI (July 25, 1968). “Humanae Vitae: Encyclical of Pope Paul VI on the Regulation of Birth”. Vatican. Archived from the original on March 19, 2011. Retrieved October 1, 2006. 
  • ^ Rosemary Radford Ruether (2006). “Women in North American Catholicism”. In Rosemary Skinner Keller. Encyclopedia of women and religion in North America. Bloomington, Ind. [u.a.]: Indiana Univ. Press. p. 132. ISBN 978-0-253-34686-5. Archived from the original on May 29, 2016. 
  • ^ Bob Digby; et al. (2001). Bob Digby, ed. Heinemann 16–19 Geography: Global Challenges Student Book (2nd ed.). Heinemann. p. 158. ISBN 978-0-435-35249-3. Archived from the original on May 12, 2016. 
  • ^ Rengel, Marian (2000). Encyclopedia of birth control. Phoenix, Ariz: Oryx Press. p. 202. ISBN 978-1-57356-255-3. Archived from the original on June 3, 2016. 
  • ^ Bennett, Jana Marguerite (2008). Water is thicker than blood : an Augustinian theology of marriage and singleness. Oxford: Oxford University Press. p. 178. ISBN 978-0-19-531543-1. Archived from the original on May 28, 2016. 
  • ^ Feldman, David M. (1998). Birth Control in Jewish Law. Lanham, MD: Jason Aronson. ISBN 0-7657-6058-4. 
  • ^ “Hindu Beliefs and Practices Affecting Health Care”. University of Virginia Health System. Archived from the original on March 23, 2004. Retrieved October 6, 2006. 
  • ^ “More Questions & Answers on Buddhism: Birth Control and Abortion”. Alan Khoo. Archived from the original on June 29, 2008. Retrieved June 14, 2008. 
  • ^ Khalid Farooq Akbar. “Family Planning and Islam: A Review”. Hamdard Islamicus. XVII (3). Archived from the original on September 26, 2006. 
  • ^ a b “World Contraception Day”. Archived from the original on August 18, 2014. 
  • ^ Hutcherson, Hilda (2002). What your mother never told you about s.e.x (1st Perigee ed.). New York: Perigee Book. p. 201. ISBN 978-0-399-52853-8. Archived from the original on June 29, 2016. 
  • ^ Rengel, Marian (2000). Encyclopedia of birth control. Phoenix, Ariz: Oryx Press. p. 65. ISBN 978-1-57356-255-3. Archived from the original on May 6, 2016. 
  • ^ Cottrell, BH (Mar–Apr 2010). “An updated review of evidence to discourage douching”. MCN. The American journal of maternal child nursing. 35 (2): 102–7; quiz 108–9. doi:10.1097/NMC.0b013e3181cae9da. PMID 20215951. 
  • ^ Alexander, William (2013). New Dimensions In Women’s Health – Book Alone (6th ed.). Jones & Bartlett Publishers. p. 105. ISBN 978-1-4496-8375-7. Archived from the original on May 6, 2016. 
  • ^ Sharkey, Harriet (2013). Need to Know Fertility and Conception and Pregnancy. HarperCollins. p. 17. ISBN 978-0-00-751686-5. Archived from the original on June 3, 2016. 
  • ^ Strange, Mary (2011). Encyclopedia of women in today’s world. Thousand Oaks, Calif.: Sage Reference. p. 928. ISBN 978-1-4129-7685-5. Archived from the original on May 15, 2016. 
  • ^ a b c Jensen, JT (October 2011). “The future of contraception: innovations in contraceptive agents: tomorrow’s hormonal contraceptive agents and their clinical implications”. American Journal of Obstetrics and Gynecology. 205 (4 Suppl): S21–5. doi:10.1016/j.ajog.2011.06.055. PMID 21961821. 
  • ^ Halpern, V; Raymond, EG; Lopez, LM (Sep 26, 2014). “Repeated use of pre- and postcoital hormonal contraception for prevention of pregnancy”. The Cochrane Database of Systematic Reviews. 9: CD007595. doi:10.1002/14651858.CD007595.pub3. PMID 25259677. 
  • ^ a b Castaño, PM; Adekunle, L (March 2010). “Transcervical sterilization”. Seminars in reproductive medicine. 28 (2): 103–9. doi:10.1055/s-0030-1248134. PMID 20352559. 
  • ^ a b Glasier, A (November 2010). “Acceptability of contraception for men: a review”. Contraception. 82 (5): 453–6. doi:10.1016/j.contraception.2010.03.016. PMID 20933119. 
  • ^ Kogan, P; Wald, M (Feb 2014). “Male contraception: history and development”. The Urologic clinics of North America. 41 (1): 145–61. doi:10.1016/j.ucl.2013.08.012. PMID 24286773. 
  • ^ Naz, RK (July 2011). “Antisperm contraceptive vaccines: where we are and where we are going?”. American journal of reproductive immunology (New York, N.Y. : 1989). 66 (1): 5–12. doi:10.1111/j.1600-0897.2011.01000.x. PMC 3110624 . PMID 21481057. 
  • ^ William J. Kovacs; Sergio R. Ojeda, eds. (2011). Textbook of endocrine physiology (6th ed.). Oxford: Oxford University Press. p. 262. ISBN 978-0-19-974412-1. Archived from the original on June 9, 2016. 
  • ^ Millar, Lila (2011). Infectious Disease Management in Animal Shelters. John Wiley & Sons. ISBN 978-1-119-94945-9. Archived from the original on May 3, 2016. 
  • ^ Ackerman, Lowell, ed. (2007). Blackwell’s five-minute veterinary practice management consult (1st ed.). Ames, Iowa: Blackwell Pub. p. 80. ISBN 978-0-7817-5984-7. Archived from the original on June 10, 2016. 
  • ^ Boyle, Rebecca (March 3, 2009). “Birth control for animals: a scientific approach to limiting the wildlife population explosion”. Popular Science. New York: PopSci.com. Archived from the original on May 25, 2012. 
  • ^ Kirkpatrick, JF; Lyda, RO; Frank, KM (July 2011). “Contraceptive vaccines for wildlife: a review”. American journal of reproductive immunology (New York, N.Y. : 1989). 66 (1): 40–50. doi:10.1111/j.1600-0897.2011.01003.x. PMID 21501279. 
  • ^ Levy, JK (July 2011). “Contraceptive vaccines for the humane control of community cat populations”. American journal of reproductive immunology (New York, N.Y. : 1989). 66 (1): 63–70. doi:10.1111/j.1600-0897.2011.01005.x. PMID 21501281. 
  • ^ “Goat ‘condoms’ save Kenyan herds”. BBC News. October 6, 2008. Archived from the original on October 6, 2008. Retrieved October 6, 2008. 
  • Further reading[edit]

    • Speroff, Leon; Darney, Philip D. (November 22, 2010). A clinical guide for contraception (5th ed.). Philadelphia, Pa.: Lippincott Williams & Wilkins. ISBN 978-1-60831-610-6.
    • Stubblefield, Phillip G.; Roncari, Danielle M. (December 12, 2011). “Family Planning”, pp. 211 – 269, in Berek, Jonathan S. (ed.) Berek & Novak’s Gynecology, 15th ed. Philadelphia: Lippincott Williams & Wilkins, ISBN 978-1-4511-1433-1.
    • Jensen, Jeffrey T.; Mishell, Daniel R. Jr. (March 19, 2012). “Family Planning: Contraception, Sterilization, and Pregnancy Termination”, pp. 215 – 272, in Lentz, Gretchen M.; Lobo, Rogerio A.; Gershenson, David M.; Katz, Vern L. (eds.) Comprehensive Gynecology, 6th ed. Philadelphia: Mosby Elsevier, ISBN 978-0-323-06986-1.
    • Gavin, L; Moskosky, S; Carter, M; Curtis, K; Glass, E (Apr 25, 2014). Godfrey, E; Marcell, A; Mautone-Smith, N; Pazol, K; Tepper, N; Zapata, L; Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, CDC. “Providing Quality Family Planning Services: Recommendations of CDC and the U.S. Office of Population Affairs”. MMWR Recommendations and Reports. 63 (RR-04): 1–54. PMID 24759690. 

    External links[edit]

    Find more aboutBirth controlat Wikipedia’s sister projects

    • Definitions from Wiktionary
    • Media from Wikimedia Commons
    • News from Wikinews
    • Quotations from Wikiquote
    • Texts from Wikisource
    • Textbooks from Wikibooks
    • Learning resources from Wikiversity
    • Data from Wikidata
    • Birth control at Curlie (based on DMOZ)
    • “WHO Fact Sheet”. July 2017. Retrieved 23 July 2017. 
    • World Health Organization Department of Reproductive Health and Research and Johns Hopkins Bloomberg School of Public Health (2011). Family planning: A global handbook for providers: Evidence-based guidance developed through worldwide collaboration (PDF) (Rev. and Updated ed.). Geneva, Switzerland: WHO and Center for Communication Programs. ISBN 978-0-9788563-7-3. 
    • Curtis, Kathryn M.; Jatlaoui, Tara C.; Tepper, Naomi K.; Zapata, Lauren B.; Horton, Leah G.; Jamieson, Denise J.; Whiteman, Maura K. (29 July 2016). “U.S. Selected Practice Recommendations for Contraceptive Use, 2016”. MMWR. Recommendations and Reports. 65 (4): 1–66. doi:10.15585/mmwr.rr6504a1. 
    • “Birth Control Comparison Chart”. Cedar River Clinics. 
    • Bulk procurement of birth control by the World Health Organization

    Anti-estrogen

    • Ormeloxifene (Centchroman)

    Post-intercourse

    • Emergency contraception (Ulipristal acetate
    • Yuzpe regimen
    • Levonorgestrel)

    Intrauterine device

    • Copper IUDs
    • Hormonal IUDs (progestogens)

    Sterilization

    • Female: Essure
    • Tubal ligation
      Male: Vasectomy

    Experimental

    • Reversible inhibition of sperm under guidance (Vasalgel)

    Long-acting reversible contraception (LARC)

    • Intrauterine device (Hormonal IUD
    • Copper IUD)
    • Contraceptive implant (Etonogestrel implant, Levonorgestrel implant)

    Sexual health

    • Female genital cutting
      • Clitoridectomy
      • Infibulation
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    Happy Birth

    Happy Birth

    Angebot Happy birthday for a stranger! At least that’s what it seems ——– Main Account is PLEASE credit LovingRobot on Toyhou.se (on site) If anything else, at least credit @/LovingHusky Only the owner of the character(s) may use

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    Birthday gift for [@vos-porwave] !!  Dusk, Ghira, and Louise belong to [@vos-porwave]

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    birth day

    today is my borthday im 16 now what the fuck

    Happy Birth

    SmallTimidBean Congratulations on arriving once more on the day that you were once born! You are a lovely human and your art style is super nostalgic and lovely, it always makes me think of Harold and the purple crayon haha. Keep being awesome!!! not counting…

    Iron Baby

    https://vimeo.com/12125147!.?.!I did all the 3D for this video( modeling, Texturing, computer animation, Fx and so on) in 3dsMax 2011 and also rendered with Vray, for this extremely brief fake trailer i did simply for enjoyable with my pal Patrick Boivin that had the idea, did the online shooting, direction as well as compositing in Adobe After Effects. We wished to see the technical level we can reach together. I utilized CAT for the animation. The initial landing shot was done by

    electronic camera projection( we had simply a photo for a fire and the background video ). I created all my HRDI pictures for the reflection making use of a fisheye lens. It took me alot of time to model the entire Iron Baby fit. I initially design the actual Iron Man and then flawed it to infant proportions. Making of readily available below: http://www.strob.net/2011/02/06/mon-making-of-du-iron-baby/ Version offered on Turbosquid: http://www.turbosquid.com/Search/Artists/Strob?referral=Strob.

    Her Olympic Goal: Find Her Birth Parents

    Her Olympic Goal: Find Her Birth Parents

    Meehyun Lee was born in South Korea and adopted by a family in Pennsylvania when she was just 1. She returned to compete for South Korea in the Olympics, hoping her birth parents might be watching.

    Nepal’s Chief Justice Sacked After He Is Accused of Faking Date of Birth

    Gopal Parajuli, the chief justice of Nepal, was fired on Wednesday after a judicial council found that he had lied about his date of birth to remain in office.

    Preterm birth

    Preterm birth, also known as premature birth, is the birth of a baby at fewer than 37 weeks gestational age.[1] These babies are known as preemies or premmies.[1] Symptoms of preterm labor include uterine contractions which occur more often than every ten minutes or the leaking of fluid from the vagina.[8] Premature infants are at greater risk for cerebral palsy, delays in development, hearing problems and sight problems.[1] These risks are greater the earlier a baby is born.[1]

    The cause of preterm birth is often not known.[2] Risk factors include diabetes, high blood pressure, being pregnant with more than one baby, being either obese or underweight, a number of vaginal infections, tobacco smoking and psychological stress, among others.[2][3] It is recommended that labor not be medically induced before 39 weeks unless required for other medical reasons.[2] The same recommendation applies to cesarean section.[2] Medical reasons for early delivery include preeclampsia.[9]

    In those at risk, the hormone progesterone, if taken during pregnancy, may prevent preterm birth.[5] Evidence does not support the usefulness of bed rest.[5][10] It is estimated that at least 75% of preterm infants would survive with appropriate treatment, and the survival rate is highest among the infants born the latest.[2] In women who might deliver between 24 and 37 weeks, corticosteroids improve outcomes.[6][11] A number of medications, including nifedipine, may delay delivery so that a mother can be moved to where more medical care is available and the corticosteroids have a greater chance to work.[12] Once the baby is born, care includes keeping the baby warm through skin to skin contact, supporting breastfeeding, treating infections and supporting breathing.[2]

    Preterm birth is the most common cause of death among infants worldwide.[1] About 15 million babies are preterm each year (5% to 18% of all deliveries).[2] Approximately 0.5% of births are extremely early periviable births, and these account for most of the deaths.[13] In many countries, rates of premature births have increased between the 1990s and 2010s.[2] Complications from preterm births resulted in 0.81 million deaths in 2015 down from 1.57 million in 1990.[7][14] The chance of survival at 22 weeks is about 6%, while at 23 weeks it is 26%, 24 weeks 55% and 25 weeks about 72%.[15] The chances of survival without any long-term difficulties are lower.[16]

    Contents

    • 1 Classification
    • 2 Signs and symptoms
      • 2.1 Complications
        • 2.1.1 Mortality and morbidity
        • 2.1.2 Specific risks for the preterm neonate
    • 3 Risk factors
      • 3.1 Maternal factors
      • 3.2 Factors during pregnancy
      • 3.3 Infection
      • 3.4 Genetics
    • 4 Diagnosis
      • 4.1 Placental alpha microglobulin-1
      • 4.2 Fetal fibronectin
      • 4.3 Ultrasound
    • 5 Prevention
      • 5.1 Before pregnancy
      • 5.2 During pregnancy
        • 5.2.1 Screening of low risk women
        • 5.2.2 Self-care
      • 5.3 Reducing existing risks
        • 5.3.1 Reducing indicated preterm birth
        • 5.3.2 Reducing spontaneous preterm birth
          • 5.3.2.1 Antibiotics
          • 5.3.2.2 Progestogens
          • 5.3.2.3 Cervical cerclage
    • 6 Management
      • 6.1 Steroids
      • 6.2 Antibiotics
      • 6.3 Tocolysis
      • 6.4 Mode of delivery
      • 6.5 Neonatal care
    • 7 Prognosis
    • 8 Epidemiology
    • 9 Society and culture
      • 9.1 Economics
      • 9.2 Notable cases
    • 10 Ethics
    • 11 References
    • 12 External links

    Classification[edit]

    Stages in prenatal development, with weeks and months numbered from last menstruation.

    In humans, the usual definition of preterm birth is birth before a gestational age of 37 complete weeks.[17] In the normal human fetus, several organ systems mature between 34 and 37 weeks, and the fetus reaches adequate maturity by the end of this period. One of the main organs greatly affected by premature birth is the lungs. The lungs are one of the last organs to mature in the womb; because of this, many premature babies spend the first days and weeks of their lives on ventilators. Therefore, a significant overlap exists between preterm birth and prematurity. Generally, preterm babies are premature and term babies are mature. Preterm babies born near 37 weeks often have no problems relating to prematurity if their lungs have developed adequate surfactant, which allows the lungs to remain expanded between breaths. Sequelae of prematurity can be reduced to a small extent by using drugs to accelerate maturation of the fetus, and to a greater extent by preventing preterm birth.

    Signs and symptoms[edit]

    A new mother holds her premature baby at Kapiolani Medical Center NICU in Honolulu, Hawaii

    Preterm birth causes a range of problems.[18]

    The main categories of causes of preterm birth are preterm labor induction and spontaneous preterm labor. Signs and symptoms of preterm labor include four or more uterine contractions in one hour. In contrast to false labour, true labor is accompanied by cervical dilatation and effacement. Also, vaginal bleeding in the third trimester, heavy pressure in the pelvis, or abdominal or back pain could be indicators that a preterm birth is about to occur. A watery discharge from the vagina may indicate premature rupture of the membranes that surround the baby. While the rupture of the membranes may not be followed by labor, usually delivery is indicated as infection (chorioamnionitis) is a serious threat to both fetus and mother. In some cases, the cervix dilates prematurely without pain or perceived contractions, so that the mother may not have warning signs until very late in the birthing process.

    A review into using uterine monitoring at home to detect contractions and possible preterm births in women at higher risk of having a preterm baby found that it did not reduce the number of preterm births.[19] The research included in the review was poor quality but it showed that home monitoring may increase the number of unplanned antenatal visits and may reduce the number of babies admitted to special care when compared with women receiving normal antenatal care.[19]

    Complications[edit]

    Mortality and morbidity[edit]

    In the U.S. where many neonatal infections and other causes of neonatal death have been markedly reduced, prematurity is the leading cause of neonatal mortality at 25%.[20] Prematurely born infants are also at greater risk for having subsequent serious chronic health problems as discussed below.

    The earliest gestational age at which the infant has at least a 50% chance of survival is referred to as the limit of viability. As NICU care has improved over the last 40 years, the limit of viability has reduced to approximately 24 weeks.[21][22] Most newborns who die, and 40% of older infants who die, were born between 20 and 25.9 weeks (gestational age), during the second trimester.[13]

    As risk of brain damage and developmental delay is significant at that threshold even if the infant survives, there are ethical controversies over the aggressiveness of the care rendered to such infants. The limit of viability has also become a factor in the abortion debate.[23]

    Specific risks for the preterm neonate[edit]

    Preterm infants usually show physical signs of prematurity in reverse proportion to the gestational age. As a result, they are at risk for numerous medical problems affecting different organ systems.

    • Neurological problems include apnea of prematurity, hypoxic-ischemic encephalopathy (HIE), retinopathy of prematurity (ROP),[24] developmental disability, transient hyperammonemia of the newborn, cerebral palsy and intraventricular hemorrhage, the latter affecting 25% of babies born preterm, usually before 32 weeks of pregnancy.[25] Mild brain bleeds usually leave no or few lasting complications, but severe bleeds often result in brain damage or even death.[25] Neurodevelopmental problems have been linked to lack of maternal thyroid hormones, at a time when their own thyroid is unable to meet postnatal needs.[26]
    • Cardiovascular complications may arise from the failure of the ductus arteriosus to close after birth: patent ductus arteriosus (PDA).
    • Respiratory problems are common, specifically the respiratory distress syndrome (RDS or IRDS) (previously called hyaline membrane disease). Another problem can be chronic lung disease (previously called bronchopulmonary dysplasia or BPD).
    • Gastrointestinal and metabolic issues can arise from neonatal hypoglycemia, feeding difficulties, rickets of prematurity, hypocalcemia, inguinal hernia, and necrotizing enterocolitis (NEC).
    • Hematologic complications include anemia of prematurity, thrombocytopenia, and hyperbilirubinemia (jaundice) that can lead to kernicterus.
    • Infection, including sepsis, pneumonia, and urinary tract infection [1]

    A study of 241 children born between 22 and 25 weeks who were currently of school age found that 46 percent had severe or moderate disabilities such as cerebral palsy, vision or hearing loss and learning problems. 34 percent were mildly disabled and 20 percent had no disabilities, while 12 percent had disabling cerebral palsy.[27][28]

    Risk factors[edit]

    The exact cause of preterm birth is difficult to determine and it may be multi-factorial. The cause of 50% of preterm births is never determined.[29] Labor is a complex process involving many factors. Four different pathways have been identified that can result in preterm birth and have considerable evidence: precocious fetal endocrine activation, uterine overdistension (placental abruption), decidual bleeding, and intrauterine inflammation/infection.[30]

    Identifying women at high risk of giving birth early would enable the health services to provide specialized care for these women to delay the birth or make sure they are in the best place to give birth (for example a hospital with a special care baby unit). Risk scoring systems have been suggested as a possible way of identifying these women. However, there is no research in this area so it is unclear whether the risk scoring systems would prolong pregnancy and reduce the numbers of preterm births or not.[31]

    Maternal factors[edit]

    A number of factors have been identified that are linked to a higher risk of a preterm birth such as being less than 18 years of age.[36] Maternal height and weight can play a role.[37]

    Further, in the US and the UK, black women have preterm birth rates of 15–18%, more than double than that of the white population. Filipinos are also at high risk of premature birth, and it is believed that nearly 11-15% of Filipinos born in the U.S. (compared to other Asians at 7.6% and whites at 7.8%) are premature.[38] Filipinos being a big risk factor is evidenced with the Philippines being the 8th highest ranking in the world for preterm births, the only non-African country in the top 10.[39] This discrepancy is not seen in comparison to other Asian groups or Hispanic immigrants and remains unexplained.[36]

    Pregnancy interval makes a difference as women with a six-month span or less between pregnancies have a two-fold increase in preterm birth.[40] Studies on type of work and physical activity have given conflicting results, but it is opined that stressful conditions, hard labor, and long hours are probably linked to preterm birth.[36]

    A history of spontaneous (i.e., miscarriage) or surgical abortion has been associated with a small increase in the risk of preterm birth, with an increased risk with increased number of abortions, although it is unclear whether the increase is caused by the abortion or by confounding risk factors (e.g., socioeconomic status).[41] Increased risk has not been shown in women who terminated their pregnancies medically.[42] Pregnancies that are unwanted or unintended are also a risk factor for preterm birth.[43]

    Adequate maternal nutrition is important. Women with a low BMI are at increased risk for preterm birth.[44] Further, women with poor nutrition status may also be deficient in vitamins and minerals. Adequate nutrition is critical for fetal development and a diet low in saturated fat and cholesterol may help reduce the risk of a preterm delivery.[45] Obesity does not directly lead to preterm birth;[46] however, it is associated with diabetes and hypertension which are risk factors by themselves.[36] To some degree those individuals may have underlying conditions (i.e., uterine malformation, hypertension, diabetes) that persist.

    Women with celiac disease have an increased risk of the development of preterm birth.[35] The risk of preterm birth is more elevated when celiac disease remains undiagnosed and untreated.[4]

    Marital status is associated with risk for preterm birth. A study of 25,373 pregnancies in Finland revealed that unmarried mothers had more preterm deliveries than married mothers (P=0.001).[34] Pregnancy outside of marriage was associated overall with a 20% increase in total adverse outcomes, even at a time when Finland provided free maternity care. A study in Quebec of 720,586 births from 1990 to 1997 revealed less risk of preterm birth for infants with legally married mothers compared with those with common-law wed or unwed parents.[47][needs update]

    Genetic make-up is a factor in the causality of preterm birth. Genetics has been a big factor into why Filipinos have a high risk of premature birth as the Filipinos have a large prevalence of mutations that help them be predisposed to premature births.[38] An intra- and transgenerational increase in the risk of preterm delivery has been demonstrated.[48] No single gene has been identified.

    Subfertility is associated with preterm birth. Couples who have tried more than 1 year versus those who have tried less than 1 year before achieving a spontaneous conception have an adjusted odds ratio of 1.35 (95% confidence interval 1.22-1.50) of preterm birth.[49] Pregnancies after IVF confers a greater risk of preterm birth than spontaneous conceptions after more than 1 year of trying, with an adjusted odds ratio of 1.55 (95% CI 1.30-1.85).[49]

    Factors during pregnancy[edit]

    The use of fertility medication that stimulates the ovary to release multiple eggs and of IVF with embryo transfer of multiple embryos has been implicated as an important factor in preterm birth. Maternal medical conditions increase the risk of preterm birth. Often labor has to be induced for medical reasons; such conditions include high blood pressure,[50] pre-eclampsia,[51] maternal diabetes,[52] asthma, thyroid disease, and heart disease.

    In a number of women anatomical issues prevent the baby from being carried to term. Some women have a weak or short cervix[50] (the strongest predictor of premature birth)[53][54][55] Women with vaginal bleeding during pregnancy are at higher risk for preterm birth. While bleeding in the third trimester may be a sign of placenta previa or placental abruption – conditions that occur frequently preterm – even earlier bleeding that is not caused by these conditions is linked to a higher preterm birth rate.[56] Women with abnormal amounts of amniotic fluid, whether too much (polyhydramnios) or too little (oligohydramnios), are also at risk.[36] The mental status of the women is of significance. Anxiety[57] and depression have been linked to preterm birth.[36]

    Finally, the use of tobacco, cocaine, and excessive alcohol during pregnancy increases the chance of preterm delivery. Tobacco is the most commonly abused drug during pregnancy and contributes significantly to low birth weight delivery.[58] Babies with birth defects are at higher risk of being born preterm.[59]

    Passive smoking and/or smoking before the pregnancy influences the probability of a preterm birth. The World Health Organization published an international study in March 2014.[60]

    Presence of anti-thyroid antibodies is associated with an increased risk preterm birth with an odds ratio of 1.9 and 95% confidence interval of 1.1–3.5.[61]

    A 2004 systematic review of 30 studies on the association between intimate partner violence and birth outcomes concluded that preterm birth and other adverse outcomes, including death, are higher among abused pregnant women than among non-abused women.[62]

    The Nigerian cultural method of abdominal massage has been shown to result in 19% preterm birth among women in Nigeria, plus many other adverse outcomes for the mother and baby.[63] This ought not be confused with massage conducted by a fully trained and licensed massage therapist or by significant others trained to provide massage during pregnancy, which has been shown to have numerous positive results during pregnancy, including the reduction of preterm birth, less depression, lower cortisol, and reduced anxiety.[64]

    Infection[edit]

    The frequency of infection in preterm birth is inversely related to the gestational age. Mycoplasma genitalium infection is associated with increased risk of preterm birth, and spontaneous abortion.[65]

    Infectious microorganisms can be ascending, hematogeneous, iatrogenic by a procedure, or retrograde through the Fallopian tubes. From the deciduas they may reach the space between the amnion and chorion, the amniotic fluid, and the fetus. A chorioamnionitis also may lead to sepsis of the mother. Fetal infection is linked to preterm birth and to significant long-term handicap including cerebral palsy.[66]

    It has been reported that asymptomatic colonization of the decidua occurs in up to 70% of women at term using a DNA probe suggesting that the presence of micro-organism alone may be insufficient to initiate the infectious response.

    As the condition is more prevalent in black women in the US and the UK, it has been suggested to be an explanation for the higher rate of preterm birth in these populations. It is opined that bacterial vaginosis before or during pregnancy may affect the decidual inflammatory response that leads to preterm birth. The condition known as aerobic vaginitis can be a serious risk factor for preterm labor; several previous studies failed to acknowledge the difference between aerobic vaginitis and bacterial vaginosis, which may explain some of the contradiction in the results.[67]

    Untreated yeast infections are associated with preterm birth.[68]

    A review into prophylactic antibiotics (given to prevent infection) in the second and third trimester of pregnancy (13–42 weeks of pregnancy) found a reduction in the number of preterm births in women with bacterial vaginosis. These antibiotics also reduced the number of waters breaking before labor in full-term pregnancies, reduced the risk of infection of the lining of the womb after delivery (endometritis), and rates of gonococcal infection. However, the women without bacterial vaginosis did not have any reduction in preterm births or pre-labor preterm waters breaking. Much of the research included in this review lost participants during follow-up so did not report the long-term effects of the antibiotics on mothers or babies. More research in this area is needed to find the full effects of giving antibiotics throughout the second and third trimesters of pregnancy.[69]

    A number of maternal bacterial infections are associated with preterm birth including pyelonephritis, asymptomatic bacteriuria, pneumonia, and appendicitis. A review into giving antibiotics in pregnancy for asymptomatic bacteriuria (urine infection with no symptoms) found the research was of very low quality but that it did suggest that taking antibiotics reduced the numbers of preterm births and babies with low birth weight.[70] Another review found that one dose of antibiotics did not seem as effective as a course of antibiotics but fewer women reported side effects from one dose.[71] This review recommended that more research is needed to discover the best way of treating asymptomatic bacteriuria.[70]

    A different review found that preterm births happened less for pregnant women who had routine testing for low genital tract infections than for women who only had testing when they showed symptoms of low genital tract infections.[72] The women being routinely tested also gave birth to fewer babies with a low birth weight. Even though these results look promising, the review was only based on one study so more research is needed into routine screening for low genital tract infections.[73]

    Also periodontal disease has been shown repeatedly to be linked to preterm birth.[74][75] In contrast, viral infections, unless accompanied by a significant febrile response, are considered not to be a major factor in relation to preterm birth.[36]

    Genetics[edit]

    There is believed to be a maternal genetic component in preterm birth.[76] Estimated heritability of timing-of-birth in women was 34%. However, the occurrence of preterm birth in families does not follow a clear inheritance pattern, thus supporting the idea that preterm birth is a non-Mendelian trait with a polygenic nature.[77]

    Diagnosis[edit]

    Placental alpha microglobulin-1[edit]

    Placental alpha microglobulin-1 (PAMG-1) has been the subject of several investigations evaluating its ability to predict imminent spontaneous preterm birth in women with signs, symptoms, or complaints suggestive of preterm labor.[78][79][80][81][82][83][84] In one investigation comparing this test to fetal fibronectin testing and cervical length measurement via transvaginal ultrasound, the test for PAMG-1 (commercially known as the PartoSure test) has been reported to be the single best predictor of imminent spontaneous delivery within 7 days of a patient presenting with signs, symptoms, or complaints of preterm labor. Specifically, the PPV, or positive predictive value, of the tests were 76%, 29%, and 30% for PAMG-1, fFN and CL, respectively (P < 0.01).[85]

    Fetal fibronectin[edit]

    Fetal fibronectin (fFN) has become an important biomarker—the presence of this glycoprotein in the cervical or vaginal secretions indicates that the border between the chorion and deciduas has been disrupted. A positive test indicates an increased risk of preterm birth, and a negative test has a high predictive value.[36] It has been shown that only 1% of women in questionable cases of preterm labor delivered within the next week when the test was negative.[86]

    Ultrasound[edit]

    Further information: Cervical incompetence

    Obstetric ultrasound has become useful in the assessment of the cervix in women at risk for premature delivery. A short cervix preterm is undesirable: A cervical length of less than 25 mm at or before 24 weeks of gestational age is the most common definition of cervical incompetence.[87]

    Prevention[edit]

    Historically efforts have been primarily aimed to improve survival and health of preterm infants (tertiary intervention). Such efforts, however, have not reduced the incidence of preterm birth. Increasingly primary interventions that are directed at all women, and secondary intervention that reduce existing risks are looked upon as measures that need to be developed and implemented to prevent the health problems of premature infants and children.[88] Smoking bans are effective in decreasing preterm births.[89]

    Before pregnancy[edit]

    Adoption of specific professional policies can immediately reduce risk of preterm birth as the experience in assisted reproduction has shown when the number of embryos during embryo transfer was limited.[88] Many countries have established specific programs to protect pregnant women from hazardous or night-shift work and to provide them with time for prenatal visits and paid pregnancy-leave. The EUROPOP study showed that preterm birth is not related to type of employment, but to prolonged work (over 42 hours per week) or prolonged standing (over 6 hours per day).[90] Also, night work has been linked to preterm birth.[91] Health policies that take these findings into account can be expected to reduce the rate of preterm birth.[88] Preconceptional intake of folic acid is recommended to reduce birth defects. There is significant evidence that long-term (> one year) use of folic acid supplement preconceptionally may reduce premature birth.[92][93][94] Reducing smoking is expected to benefit pregnant women and their offspring.[88]

    During pregnancy[edit]

    Healthy eating can be instituted at any stage of the pregnancy including nutritional adjustments, use of vitamin supplements, and smoking cessation.[88] Calcium supplementation in women who have low dietary calcium reduces the number of negative outcomes including preterm birth, pre-eclampsia, and maternal death.[95] The World Health Organization (WHO) suggests 1.5-2 g of calcium supplements daily, for pregnant women who have low levels calcium in their diet.[95] Supplemental intake of C and E vitamins have not been found to reduce preterm birth rates.[96] Different strategies are used in the administration of prenatal care, and future studies need to determine if the focus can be on screening for high-risk women, or widened support for low-risk women, or to what degree these approaches can be merged.[88] While periodontal infection has been linked with preterm birth, randomized trials have not shown that periodontal care during pregnancy reduces preterm birth rates.[88]

    Screening of low risk women[edit]

    Screening for asymptomatic bacteriuria followed by appropriate treatment reduces pyelonephritis and reduces the risk of preterm birth.[97] Extensive studies have been carried out to determine if other forms of screening in low-risk women followed by appropriate intervention are beneficial, including: Screening for and treatment of Ureaplasma urealyticum, group B streptococcus, Trichomonas vaginalis, and bacterial vaginosis did not reduce the rate of preterm birth.[88] Routine ultrasound examination of the length of the cervix identifies patients at risk, but cerclage is not proven useful, and the application of a progestogen is under study.[88] Screening for the presence of fibronectin in vaginal secretions is not recommended at this time in women at low risk.

    Self-care[edit]

    Self-care methods to reduce the risk of preterm birth include proper nutrition, avoiding stress, seeking appropriate medical care, avoiding infections, and the control of preterm birth risk factors (e.g. working long hours while standing on feet, carbon monoxide exposure, domestic abuse, and other factors). Self-monitoring vaginal pH followed by yogurt treatment or clindamycin treatment if the pH was too high all seem to be effective at reducing the risk of preterm birth.[98][99] Additional support during pregnancy does not appear to prevent low birthweight or preterm birth.[100]

    Reducing existing risks[edit]

    Women are identified to be at increased risk for preterm birth on the basis of their past obstetrical history or the presence of known risk factors. Preconception intervention can be helpful in selected patients in a number of ways. Patients with certain uterine anomalies may have a surgical correction (i.e. removal of a uterine septum), and those with certain medical problems can be helped by optimizing medical therapies prior to conception, be it for asthma, diabetes, hypertension and others.

    Reducing indicated preterm birth[edit]

    A number of agents have been studied for the secondary prevention of indicated preterm birth. Trials using low-dose aspirin, fish oil, vitamin C and E, and calcium to reduce preeclampsia demonstrated some reduction in preterm birth only when low-dose aspirin was used.[88] Interestingly, even if agents such as calcium or antioxidants were able to reduce preeclampsia, a resulting decrease in preterm birth was not observed.[88]

    Reducing spontaneous preterm birth[edit]

    Reduction in activity by the mother – pelvic rest, limited work, bed rest – may be recommended although there is no evidence it is useful with some concerns it is harmful.[101] Increasing medical care by more frequent visits and more education has not been shown to reduce preterm birth rates.[100] Use of nutritional supplements such as omega-3 polyunsaturated fatty acids is based on the observation that populations who have a high intake of such agents are at low risk for preterm birth, presumably as these agents inhibit production of proinflammatory cytokines. A randomized trial showed a significant decline in preterm birth rates,[102] and further studies are in the making.

    Antibiotics[edit]

    While antibiotics can get rid of bacterial vaginosis in pregnancy, this does not appear to change the risk of preterm birth.[103] It has been suggested that chronic chorioamnionitis is not sufficiently treated by antibiotics alone (and therefore they cannot ameliorate the need for preterm delivery in this condition).[88]

    Progestogens[edit]

    Progestogens, often given in the form of progesterone or hydroxyprogesterone caproate, relaxes the uterine musculature, maintains cervical length, and has anti-inflammatory properties, and thus exerts activities expected to be beneficial in reducing preterm birth. Two meta-analyses demonstrated a reduction in the risk of preterm birth in women with recurrent preterm birth by 40–55%.[104][105]

    Progestogen supplementation also reduces the frequency of preterm birth in pregnancies where there is a short cervix.[106] However, progestogens are not effective in all populations, as a study involving twin gestations failed to see any benefit.[107]

    Cervical cerclage[edit]

    In preparation for childbirth, the woman’s cervix shortens. Preterm cervical shortening is linked to preterm birth and can be detected by ultrasonography. Cervical cerclage is a surgical intervention that places a suture around the cervix to prevent its shortening and widening. Numerous studies have been performed to assess the value of cervical cerclage and the procedure appears helpful primarily for women with a short cervix and a history of preterm birth.[106][108] Instead of a prophylactic cerclage, women at risk can be monitored during pregnancy by sonography, and when shortening of the cervix is observed, the cerclage can be performed.[88]

    Management[edit]

    About 75% of nearly a million deaths due to preterm deliver would survive if provided warmth, breastfeeding, treatments for infection, and breathing support.[109] If a baby has cardiac arrest at birth and is before 23 weeks or less than 400 gms attempts at resuscitation are not indicated.[110]

    Tertiary interventions are aimed at women who are about to go into preterm labor, or rupture the membranes or bleed preterm. The use of the fibronectin test and ultrasonography improves the diagnostic accuracy and reduces false-positive diagnosis. While treatments to arrest early labor where there is progressive cervical dilatation and effacement will not be effective to gain sufficient time to allow the fetus to grow and mature further, it may defer delivery sufficiently to allow the mother to be brought to a specialized center that is equipped and staffed to handle preterm deliveries.[111] In a hospital setting women are hydrated via intravenous infusion (as dehydration can lead to premature uterine contractions).[112]

    Steroids[edit]

    Severely premature infants may have underdeveloped lungs because they are not yet producing their own surfactant. This can lead directly to respiratory distress syndrome, also called hyaline membrane disease, in the neonate. To try to reduce the risk of this outcome, pregnant mothers with threatened premature delivery prior to 34 weeks are often administered at least one course of glucocorticoids, a steroid that crosses the placental barrier and stimulates the production of surfactant in the lungs of the baby.[11] Steroid use up to 37 weeks is also recommended by the American Congress of Obstetricians and Gynecologists.[11] Typical glucocorticoids that would be administered in this context are betamethasone or dexamethasone, often when the pregnancy has reached viability at 23 weeks.

    In cases where premature birth is imminent, a second “rescue” course of steroids may be administered 12 to 24 hours before the anticipated birth. There are still some concerns about the efficacy and side-effects of a second course of steroids, but the consequences of RDS are so severe that a second course is often viewed as worth the risk. A 2015 Cochrane review supports the use of repeat dose(s) of prenatal corticosteroids for women still at risk of preterm birth seven days or more after an initial course.[113]

    Beside reducing respiratory distress, other neonatal complications are reduced by the use of glucocorticosteroids, namely intraventricular bleeding, necrotising enterocolitis, and patent ductus arteriosus.[114] A single course of antenatal corticosteroids could be considered routine for preterm delivery, but there are some concerns about applicability of this recommendation to low-resource settings with high rates of infections.[114] It remains unclear whether one corticosteroid (or one particular regimen) has advantages over another.[115]

    Concerns about adverse effects of prenatal corticosteroids include increased risk for maternal infection, difficulty with diabetic control, and possible long-term effects on neurodevelopmental outcomes for the infants. There is ongoing discussion about when steroids should be given (i.e. only antenatally or postnatally too) and for how long (i.e. single course or repeated administration). Despite these unknowns, there is a consensus that the benefits of a single course of prenatal glucocorticosteroids vastly outweigh the potential risks.[116][117][118]

    Antibiotics[edit]

    The routine administration of antibiotics to all women with threatened preterm labor reduces the risk of the baby to get infected with group B streptococcus and has been shown to reduce related mortality rates.[119]

    When membranes rupture prematurely, obstetrical management looks for development of labor and signs of infection. Prophylactic antibiotic administration has been shown to prolong pregnancy and reduced neonatal morbidity with rupture of membranes at less than 34 weeks.[120] Because of concern about necrotizing enterocolitis, amoxicillin or erythromycin has been recommended, but not amoxicillin + clavulanic acid (co-amoxiclav).[120]

    Tocolysis[edit]

    A number of medications may be useful to delay delivery including: NSAIDs, calcium channel blockers, beta mimetics, and atosiban.[121] Tocolysis rarely delays delivery beyond 24–48 hours.[122] This delay however may be sufficient to allow the pregnant woman to be transferred to a center specialized for management of preterm deliveries and give administered corticosteroids to reduce neonatal organ immaturity. Meta-analyses indicate that calcium-channel blockers and an oxytocin antagonist can delay delivery by 2–7 days, and β2-agonist drugs delay by 48 hours but carry more side effects.[88][123] Magnesium sulfate does not appear to be useful to prevent preterm birth.[124] It use before delivery however does appear to decrease the risk of cerebral palsy.[125]

    Mode of delivery[edit]

    The routine use of cesarean section for early delivery of infants expected to have very low birth weight is controversial,[88][126] and a decision concerning the route and time of delivery probably needs to be made on a case by case basis.

    Neonatal care[edit]

    After delivery, plastic wraps or warm mattresses are useful to keep the infant warm on their way to the NICU.[127] In developed countries premature infants are usually cared for in a neonatal intensive care unit (NICU). The physicians who specialize in the care of very sick or premature babies are known as neonatologists. In the NICU, premature babies are kept under radiant warmers or in incubators (also called isolettes), which are bassinets enclosed in plastic with climate control equipment designed to keep them warm and limit their exposure to germs. Modern neonatal intensive care involves sophisticated measurement of temperature, respiration, cardiac function, oxygenation, and brain activity. Treatments may include fluids and nutrition through intravenous catheters, oxygen supplementation, mechanical ventilation support, and medications. In developing countries where advanced equipment and even electricity may not be available or reliable, simple measures such as kangaroo care (skin to skin warming), encouraging breastfeeding, and basic infection control measures can significantly reduce preterm morbidity and mortality. Bili lights may also be used to treat newborn jaundice (hyperbilirubinemia).

    Water can be carefully provided to prevent dehydration but no so much to increase risks of side effects.[128]

    In a 2012 policy statement, the American Academy of Pediatrics recommended feeding preterm infants human milk, finding “significant short- and long-term beneficial effects,” including lower rates of necrotizing enterocolitis (NEC). [129]

    Prognosis[edit]

    The chance of survival at 22 weeks is about 6%, while at 23 weeks it is 26%, 24 weeks 55% and 25 weeks about 72%.[15] The chances of survival without long-term difficulties is less.[16] In the developed world overall survival is about 90% while in low-income countries survival rates are about 10%.[109]

    Some children will adjust well during childhood and adolescence,[130] although disability is more likely nearer the limits of viability. A large study followed children born between 22 and 25 weeks until the age of 6 years old. Of these children, 46 percent had moderate to severe disabilities such as cerebral palsy, vision or hearing loss and learning disabilities, 34 percent had mild disabilities, and 20 percent had no disabilities. 12 percent had disabling cerebral palsy.[28]

    As survival has improved, the focus of interventions directed at the newborn has shifted to reduce long-term disabilities, particularly those related to brain injury.[130] Some of the complications related to prematurity may not be apparent until years after the birth. A long-term study demonstrated that the risks of medical and social disabilities extend into adulthood and are higher with decreasing gestational age at birth and include cerebral palsy, intellectual disability, disorders of psychological development, behavior, and emotion, disabilities of vision and hearing, and epilepsy.[131] Standard intelligence tests showed that 41 percent of children born between 22 and 25 weeks had moderate or severe learning disabilities when compared to the test scores of a group of similar classmates who were born at full-term.[28] It is also shown that higher levels of education were less likely to be obtained with decreasing gestational age at birth.[131] People born prematurely may be more susceptible to developing depression as teenagers.[132] Some of these problems can be described as being within the executive domain and have been speculated to arise due to decreased myelinization of the frontal lobes.[133] Studies of people born premature and investigated later with MRI brain imaging, demonstrate qualitative anomalies of brain structure and grey matter deficits within temporal lobe structures and the cerebellum that persist into adolescence.[134] Throughout life they are more likely to require services provided by physical therapists, occupational therapists, or speech therapists.[130]

    Despite the neurosensory, mental and educational problems studied in school age and adolescent children born extremely preterm, the majority of preterm survivors born during the early years of neonatal intensive care are found to do well and to live fairly normal lives in young adulthood.[135] Young adults born preterm seem to acknowledge that they have more health problems than their peers, yet feel the same degree of satisfaction with their quality of life.[136]

    Beyond the neurodevelopmental consequences of prematurity, infants born preterm have a greater risk for many other health problems. For instance, children born prematurely have an increased risk for developing chronic kidney disease.[137]

    Epidemiology[edit]

    Disability-adjusted life year for prematurity and low birth weight per 100,000 inhabitants in 2004.[138]

      no data
      less than 120
      120-240
      240-360
      360-480
      480-600
      600-720
      720-840
      840-960
      960-1080
      1080-1200
      1200-1500
      more than 1500

    Preterm birth complicates the births of infants worldwide affecting 5% to 18% of births.[68] In Europe and many developed countries the preterm birth rate is generally 5–9%, and in the USA it has even risen to 12–13% in the last decades.[139]

    As weight is easier to determine than gestational age, the World Health Organization tracks rates of low birth weight (< 2,500 grams), which occurred in 16.5 percent of births in less developed regions in 2000.[140] It is estimated that one-third of these low birth weight deliveries are due to preterm delivery. Weight generally correlates to gestational age, however, infants may be underweight for other reasons than a preterm delivery. Neonates of low birth weight (LBW) have a birth weight of less than 2500 g (5 lb 8 oz) and are mostly but not exclusively preterm babies as they also include small for gestational age (SGA) babies. Weight-based classification further recognizes Very Low Birth Weight (VLBW) which is less than 1500 g, and Extremely Low Birth Weight (ELBW) which is less than 1000 g.[141] Almost all neonates in these latter two groups are born preterm.

    Complications from preterm births resulted in 0.74 million deaths in 2013 down from 1.57 million in 1990.[14]

    Society and culture[edit]

    Economics[edit]

    Preterm birth is a significant cost factor in healthcare, not even considering the expenses of long-term care for individuals with disabilities due to preterm birth. A 2003 study in the US determined neonatal costs to be $224,400 for a newborn at 500–700 g versus $1,000 at over 3,000 g. The costs increase exponentially with decreasing gestational age and weight.[142] The 2007 Institute of Medicine report Preterm Birth [143] found that the 550,000 preemies born each year in the U.S. run up about $26 billion in annual costs, mostly related to care in NICUs, but the real tab may top $50 billion.[144]

    Notable cases[edit]

    James Elgin Gill (born on 20 May 1987 in Ottawa, Ontario, Canada) was the earliest premature baby in the world, until that record was broken in 2014. He was 128 days premature (21 weeks and 5 days gestation) and weighed 1 pound 6 ounces (624 g). He survived.[145][146]

    In 2014, a baby girl born in San Antonio became the youngest premature baby in the world. The daughter of Courtney Stensrud was born at 21 weeks 4 days and weighed 410 grams (less than a pound). Kaashif Ahmad resuscitated the baby after she was born. As of 2017, the girl was in preschool and on par with her peers.[147]

    Amillia Taylor is also often cited as the most premature baby.[148] She was born on 24 October 2006 in Miami, Florida, at 21 weeks and 6 days gestation.[149] This report has created some confusion as her gestation was measured from the date of conception (through in vitro fertilization) rather than the date of her mother’s last menstrual period making her appear 2 weeks younger than if gestation was calculated by the more common method.[132] At birth, she was 9 inches (22.9 cm) long and weighed 10 ounces (283 grams).[148] She suffered digestive and respiratory problems, together with a brain hemorrhage. She was discharged from the Baptist Children’s Hospital on 20 February 2007.[148]

    The record for the smallest premature baby to survive was held for a considerable amount of time by Madeline Mann, who was born in 1989 at 26 weeks weighing 9.9 oz (280 g) and 9.5 inches (24.1 cm) long.[150] This record was broken in September 2004 by Rumaisa Rahman, who was born in the same hospital[151] at 25 weeks gestation. At birth, she was eight inches (20 cm) long and weighed 244 grams (8.6 ounces). Her twin sister was also a small baby, weighing 563 grams (1 pound 4 ounces) at birth. During pregnancy their mother had suffered from pre-eclampsia, which causes dangerously high blood pressure putting the baby into distress and requiring birth by caesarean section. The larger twin left the hospital at the end of December, while the smaller remained there until 10 February 2005 by which time her weight had increased to 1.18 kg (2.6 lb).[152] Generally healthy, the twins had to undergo laser eye surgery to correct vision problems, a common occurrence among premature babies.

    The world’s smallest premature boy to survive was born in February 2009 at Children’s Hospitals and Clinics of Minnesota in Minneapolis, Minnesota. Jonathon Whitehill was born at 25 weeks gestation with a weight of 310 grams (10.9 ounces). He was hospitalized in the Neonatal Intensive Care Unit for five months, and then discharged.[153]

    Historical figures who were born prematurely include Johannes Kepler (born in 1571 at 7 months gestation), Isaac Newton (born in 1642, small enough to fit into a quart mug, according to his mother), Winston Churchill (born in 1874 at 7 months gestation), Anna Pavlova (born in 1885 at 7 months gestation),[154] Mark Twain (born 1835 two months early), Albert Einstein (born 1879 premature), and Stevie Wonder (born 1950 six weeks early).[155]

    Ethics[edit]

    The transformation of medical care means that extremely premature and very ill babies have better chances of survival than ever before. But it is difficult to predict which babies will die and which will live, though possibly with severe disabilities. As a consequence, families and health professionals have to make complex decisions about how much intervention is necessary or justifiable.

    The most difficult decisions are about whether or not to resuscitate a premature baby and admit him or her to neonatal intensive care, or whether to withdraw intensive care and give the child palliative care.

    This is discussed at great length in a report “Critical care decisions in fetal and neonatal medicine: ethical issues”[156] produced by the London-based Nuffield Council for Bioethics.

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  • ^ Cervical incompetence Archived 7 March 2014 at the Wayback Machine. from Radiopaedia. Authors: Dr Praveen Jha and Dr Laughlin Dawes et al. Retrieved Feb 2014
  • ^ a b c d e f g h i j k l m n o Iams JD, Romero R, Culhane JF, Goldenberg RL (2008). “Primary, secondary, and tertiary interventions to reduce the morbidity and mortality of preterm birth”. The Lancet. 371 (9607): 164–175. doi:10.1016/S0140-6736(08)60108-7. PMID 18191687. 
  • ^ Been JV, Nurmatov UB, Cox B, Nawrot TS, van Schayck CP, Sheikh A (May 3, 2014). “Effect of smoke-free legislation on perinatal and child health: a systematic review and meta-analysis”. Lancet. 383 (9928): 1549–60. doi:10.1016/S0140-6736(14)60082-9. PMID 24680633. 
  • ^ Saurel-Cubizolles MJ, Zeitlin J, Lelong N, Papiernik E, Di Renzo GC, Bréart G (2004). “Employment, working conditions, and preterm birth: results from the Europop case-control survey”. Journal of Epidemiology and Community Health. 58 (5): 395–401. doi:10.1136/jech.2003.008029. PMC 1732750 . PMID 15082738. 
  • ^ Other Complications include:
    • Jaundice Of Prematurity
    • Atrial septal defects commonly seen in babies with bronchopulmonary dysplasia because their lungs are so fragile.
    • GER Gastroesophageal reflux
    • Patent Ductus Arterosis
    • Seizures
    • Immature GI system so feeding from an (NG) tube or nasogastric tube may help make feeding easier on the babies’ tummy. Also theirs[clarification needed] TPN feeding or Total Parenteral Nutrition is made up of lipids, calories, good fats calcium, magnesium sulfate and other vitamins including B and C. Neonatalogists work with the family as a whole instead of just the neonate or baby whose systems are to immature to actually swallow food so babies between 23-28 weeks are fed through a neonatal gastric tube from the babies nose to the stomach. In some neonates, there are disabilities from varying conditions of the baby this depends on the gestational age the babies delivered a.uUsually, women with severe enough preeclampsia will deliver earlier than normal and those mothers worry greatly because of all of their rumors about NICUs and babies needing wheelchairs glasses and also needing medicines for seizures and ADD/ADHD, Borderline Personality Disorder, anxiety disorders.

    Pompeii LA, Savitz DA, Evenson KR, Rogers B, McMahon M (2005). “Physical exertion at work and the risk of preterm delivery and small-for-gestational-age birth”. Obstetrics & Gynecology. 106 (6): 1279–1288. doi:10.1097/01.AOG.0000189080.76998.f8. PMID 16319253. 

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  • ^ Dodd JM, Jones L, Flenady V, Cincotta R, Crowther CA (2013). “Prenatal administration of progesterone for preventing preterm birth”. Cochrane Database of Systematic Reviews. 7 (7): CD004947. doi:10.1002/14651858.CD004947.pub3. PMID 23903965. Archived from the original on 20 February 2017. 
  • ^ Mackenzie R, Walker M, Armson A, Hannah ME (2006). “Progesterone for the prevention of preterm birth among women at increased. A systematic review and meta-analysis of randomized controlled trials”. American Journal of Obstetrics & Gynecology. 194 (5): 1234–1242. doi:10.1016/j.ajog.2005.06.049. PMID 16647905. 
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  • ^ a b “World Health Organization”. November 2015. Archived from the original on 18 July 2016. 
  • ^ Mancini, ME; Diekema, DS; Hoadley, TA; Kadlec, KD; Leveille, MH; McGowan, JE; Munkwitz, MM; Panchal, AR; Sayre, MR; Sinz, EH (3 November 2015). “Part 3: Ethical Issues: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care”. Circulation. 132 (18 Suppl 2): S383–96. doi:10.1161/cir.0000000000000254. PMID 26472991. 
  • ^ Phibbs CS, Baker LC, Caughey AB, Danielsen B, Schmitt SK, Phibbs RH (2007). “Level and volume of neonatal intensive care and mortality in very-low-birth-weight infants”. New England Journal of Medicine. 356 (21): 2165–2175. doi:10.1056/NEJMsa065029. PMID 17522400. 
  • ^ Stan, Catalin M.; Boulvain, Michel; Pfister, Riccardo; Hirsbrunner-Almagbaly, Pascale (2013-11-04). “Hydration for treatment of preterm labour”. The Cochrane Database of Systematic Reviews (11): CD003096. doi:10.1002/14651858.CD003096.pub2. ISSN 1469-493X. PMID 24190310. 
  • ^ Crowther, Caroline A.; McKinlay, Christopher J. D.; Middleton, Philippa; Harding, Jane E. (2015-07-05). “Repeat doses of prenatal corticosteroids for women at risk of preterm birth for improving neonatal health outcomes”. The Cochrane Database of Systematic Reviews (7): CD003935. doi:10.1002/14651858.CD003935.pub4. ISSN 1469-493X. PMID 26142898. 
  • ^ a b Roberts, Devender; Brown, Julie; Medley, Nancy; Dalziel, Stuart R. (21 Mar 2017). “Antenatal corticosteroids for accelerating fetal lung maturation for women at risk of preterm birth”. The Cochrane Database of Systematic Reviews. 3: CD004454. doi:10.1002/14651858.CD004454.pub3. ISSN 1469-493X. PMID 28321847. 
  • ^ Brownfoot, Fiona C.; Gagliardi, Daniela I.; Bain, Emily; Middleton, Philippa; Crowther, Caroline A. (2013-08-29). “Different corticosteroids and regimens for accelerating fetal lung maturation for women at risk of preterm birth”. The Cochrane Database of Systematic Reviews (8): CD006764. doi:10.1002/14651858.CD006764.pub3. ISSN 1469-493X. PMID 23990333. 
  • ^ “Archived copy”. Archived from the original on 9 July 2017. Retrieved 18 July 2017. 
  • ^ “Archived copy”. Archived from the original on 18 January 2017. Retrieved 18 July 2017. 
  • ^ McGoldrick, Emma; Brown, Julie; Middleton, Philippa; McKinlay, Christopher JD; Haas, David M; Crowther, Caroline A (17 April 2016). “Antenatal corticosteroids for fetal lung maturation: an overview of Cochrane reviews”. Cochrane Database of Systematic Reviews. John Wiley & Sons, Ltd (4). doi:10.1002/14651858.cd012156. ISSN 1465-1858. Archived from the original on 10 September 2017. 
  • ^ Schrag S, Gorwitz R, Fultz-Butts K, Schuchat A (2002). “Prevention of perinatal group B streptococcal disease. Revised guidelines from CDC”. MMWR. Recommendations and Reports. 51 (RR-11): 1–22. PMID 12211284. 
  • ^ a b Kenyon SL, Taylor DJ, Tarnow-Mordi W (2001). “Broad-spectrum antibiotics for preterm, prelabour rupture of fetal membranes: the ORACLE I randomised trial. ORACLE Collaborative Group”. The Lancet. 357 (9261): 979–988. doi:10.1016/S0140-6736(00)04233-1. PMID 11293641. 
  • ^ Haas DM, Caldwell DM, Kirkpatrick P, McIntosh JJ, Welton NJ (Oct 9, 2012). “Tocolytic therapy for preterm delivery: systematic review and network meta-analysis”. BMJ (Clinical research ed.). 345: e6226. doi:10.1136/bmj.e6226. PMC 4688428 . PMID 23048010. 
  • ^ Simhan HN, Caritis SN (2007). “Prevention of Preterm Delivery”. New England Journal of Medicine. 357 (5): 477–487. doi:10.1056/NEJMra050435. PMID 17671256. 
  • ^ Li X, Zhang Y, Shi Z (February 2005). “Ritodrine in the treatment of preterm labour: a meta-analysis”. Indian J. Med. Res. 121 (2): 120–7. PMID 15756046. 
  • ^ Crowther CA, Brown J, McKinlay CJ, Middleton P (Aug 15, 2014). “Magnesium sulphate for preventing preterm birth in threatened preterm labour”. The Cochrane Database of Systematic Reviews. 8 (8): CD001060. doi:10.1002/14651858.CD001060.pub2. PMID 25126773. 
  • ^ Crowther, CA; Middleton, PF; Voysey, M; Askie, L; Duley, L; Pryde, PG; Marret, S; Doyle, LW; AMICABLE, Group. (October 2017). “Assessing the neuroprotective benefits for babies of antenatal magnesium sulphate: An individual participant data meta-analysis”. PLoS medicine. 14 (10): e1002398. doi:10.1371/journal.pmed.1002398. PMID 28976987. 
  • ^ Alfirevic, Zarko; Milan, Stephen J.; Livio, Stefania (2012-06-13). “Caesarean section versus vaginal delivery for preterm birth in singletons”. The Cochrane Database of Systematic Reviews (6): CD000078. doi:10.1002/14651858.CD000078.pub2. ISSN 1469-493X. PMC 4164504 . PMID 22696314. 
  • ^ McCall EM, Alderdice F, Halliday HL, Jenkins JG, Vohra S (Mar 17, 2010). “Interventions to prevent hypothermia at birth in preterm and/or low birthweight infants”. The Cochrane Database of Systematic Reviews (3): CD004210. doi:10.1002/14651858.CD004210.pub4. PMID 20238329. 
  • ^ Bell EF, Acarregui MJ (4 December 2014). “Restricted versus liberal water intake for preventing morbidity and mortality in preterm infants”. The Cochrane Database of Systematic Reviews. 12 (12): CD000503. doi:10.1002/14651858.CD000503.pub3. PMID 25473815. 
  • ^ American Academy of Pediatrics, Section on Breastfeeding (2012). “Breastfeeding and the Use of Human Milk”. Pediatrics. 129 (3): e827–e841. doi:10.1542/peds.2011-3552. PMID 22371471. Archived from the original on 27 July 2013. Retrieved 25 July 2013. Meta-analyses of 4 randomized clinical trials performed over the period 1983 to 2005 support the conclusion that feeding preterm infants human milk is associated with a significant reduction (58%) in the incidence of NEC. 
  • ^ a b c Saigal S, Doyle LW (2008). “An overview of mortality and sequelae of preterm birth from infancy to adulthood”. The Lancet. 371 (9608): 261–269. doi:10.1016/S0140-6736(08)60136-1. PMID 18207020. 
  • ^ a b Moster D, Lie RT, Markestad T (2008). “Long-Term Medical and Social Consequences of Preterm Birth”. New England Journal of Medicine. 359 (3): 262–273. doi:10.1056/NEJMoa0706475. PMID 18635431. 
  • ^ a b “Depression linked to premature birth”. The Age. Melbourne. 4 May 2004. Archived from the original on 8 April 2009. Retrieved 16 December 2008. 
  • ^ Böhm B, Katz-Salamon M, Institute K, Smedler AC, Lagercrantz H, Forssberg H (2002). “Developmental Risks and Protective Factors for Influencing cognitive outcome at 5,5 years of age in very-low-birthweight children”. Developmental Medicine & Child Neurology. 44 (8): 508–516. doi:10.1017/S001216220100247X. PMID 12206615. 
  • ^ Spencer MD, Moorhead TW, Gibson RJ, McIntosh AM, Sussmann JE, Owens DG, Lawrie SM, Johnstone EC (30 January 2008). “Low birthweight and preterm birth in young people with special educational needs: a magnetic resonance imaging analysis”. BMC Medicine. 6 (1): 1. doi:10.1186/1741-7015-6-1. PMC 2241838 . PMID 18234075. Archived from the original on 2 November 2010. Retrieved 26 July 2011. 
  • ^ Hack, Maureen (2009-10-01). “Adult Outcomes of Preterm Children”. Journal of Developmental & Behavioral Pediatrics. 30 (5): 460–470. doi:10.1097/dbp.0b013e3181ba0fba. ISSN 0196-206X. 
  • ^ Saigal, Saroj. “Quality of life of former premature infants during adolescence and beyond”. Early Human Development. 89 (4): 209–213. doi:10.1016/j.earlhumdev.2013.01.012. 
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  • ^ Richard E. Behrman, Adrienne Stith Butler, Editors, Committee on Understanding Premature Birth and Assuring Healthy Outcomes. Preterm Birth: Causes, Consequences, and Prevention Archived 5 June 2011 at the Wayback Machine.. Institute of Medicine. The National Academies Press, 2007. Retrieved 2010-1-14.
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  • ^ Preemies (Second ed.). [full citation needed]
  • ^ Nuffield Council for Bioethics (2006). “Critical care decisions in fetal and neonatal medicine”. Critical care decisions in fetal and neonatal medicine (PDF). Archived (PDF) from the original on 26 June 2013. 
  • External links[edit]

    • Preterm Birth: Causes, Consequences and Prevention (PDF). Institute of Medicine. 

    Maternal care related to the
    fetus and amniotic cavity

    • amniotic fluid
      • Oligohydramnios
      • Polyhydramnios
    • Braxton Hicks contractions
    • chorion / amnion
      • Amniotic band syndrome
      • Chorioamnionitis
      • Chorionic hematoma
      • Monoamniotic twins
      • Premature rupture of membranes
    • Obstetrical bleeding
      • Antepartum
    • placenta
      • Circumvallate placenta
      • Monochorionic twins
      • Placenta praevia
      • Placental abruption
      • Twin-to-twin transfusion syndrome

    Labor

    • Amniotic fluid embolism
    • Cephalopelvic disproportion
    • Dystocia
      • Shoulder dystocia
    • Fetal distress
    • Locked twins
    • Obstetrical bleeding
      • Postpartum
    • Pain management during childbirth
    • placenta
      • Placenta accreta
    • Preterm birth
    • Postmature birth
    • Umbilical cord prolapse
    • Uterine rupture
    • Vasa praevia

    Puerperal

    • Breastfeeding difficulties
      • Low milk supply
      • Cracked nipples
    • Breast engorgement
    • Childbirth-related posttraumatic stress disorder
    • Diastasis symphysis pubis
    • Postpartum bleeding
    • Peripartum cardiomyopathy
    • Postpartum depression
    • Postpartum thyroiditis
    • Puerperal fever
    • Puerperal mastitis

    Other

    • Concomitant conditions
      • Diabetes mellitus
      • Systemic lupus erythematosus
      • Thyroid disorders
    • Maternal death
    • Sexual activity during pregnancy

    Length of gestation
    and fetal growth

    • Small for gestational age/Large for gestational age
    • Preterm birth/Postmature birth
    • Intrauterine growth restriction

    Birth trauma

    • scalp
      • Cephalhematoma
      • Chignon
      • Caput succedaneum
      • Subgaleal hemorrhage
    • Brachial plexus lesion
      • Erb’s palsy
      • Klumpke paralysis

    By system

    Infectious

    • Vertically transmitted infection
    • Neonatal infection
      • Congenital rubella syndrome
      • Neonatal herpes simplex
      • Mycoplasma hominis infection
      • Ureaplasma urealyticum infection
    • Omphalitis
    • Neonatal sepsis
      • Group B streptococcal infection
    • Neonatal conjunctivitis

    Other

    • Miscarriage
    • Perinatal mortality
      • Stillbirth
      • Infant mortality
    • Neonatal withdrawal


    Birth

    For other uses, see Birth (disambiguation) and Childbirth.

    Lambing: the mother licks the first lamb while giving birth to the second

    Birth is the act or process of bearing or bringing forth offspring.[1] In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the fetus at a developmental stage when it is ready to feed and breathe. In some species the offspring is precocial and can move around almost immediately after birth but in others it is altricial and completely dependent on parenting. In marsupials, the fetus is born at a very immature stage after a short gestational period and develops further in its mother’s womb’s pouch.

    It is not only mammals that give birth. Some reptiles, amphibians, fish and invertebrates carry their developing young inside them. Some of these are ovoviviparous, with the eggs being hatched inside the mother’s body, and others are viviparous, with the embryo developing inside her body, as in mammals.

    Contents

    • 1 Mammals
      • 1.1 Human childbirth
      • 1.2 Cattle
      • 1.3 Dogs
      • 1.4 Marsupials
    • 2 Other animals
    • 3 See also
    • 4 References
    • 5 Cited texts

    Mammals[edit]

    Large mammals, such as primates, cattle, horses, some antelopes, giraffes, hippopotamuses, rhinoceroses, elephants, seals, whales, dolphins, and porpoises, generally are pregnant with one offspring at a time, although they may have twin or multiple births on occasion. In these large animals, the birth process is similar to that of a human, though in most the offspring is precocial. This means that it is born in a more advanced state than a human baby and is able to stand, walk and run (or swim in the case of an aquatic mammal) shortly after birth.[2] In the case of whales, dolphins and porpoises, the single calf is normally born tail first which minimises the risk of drowning.[3] The mother encourages the newborn calf to rise to the surface of the water to breathe.[4]

    Most smaller mammals have multiple births, producing litters of young which may number twelve or more. In these animals, each fetus is surrounded by its own amniotic sac and has a separate placenta. This separates from the wall of the uterus during labor and the fetus works its way towards the birth canal.[citation needed]

    Large mammals which give birth to twins is much more rare, but it does occur occasionally even for mammals as large as elephants. In April 2018, approximately 8-month old elephant twins were sighted joining their mother’s herd in the Tarangire National Park of Tanzania, estimated to have been born in August 2017.[5]

    Human childbirth[edit]

    Main article: Childbirth
    Further information: Adaptation to extrauterine life

    An illustration of normal head-first presentation by the obstetrician William Smellie from about 1792. The membranes have ruptured and the cervix is fully dilated.

    Humans usually produce a single offspring at a time. The mother’s body is prepared for birth by hormones produced by the pituitary gland, the ovary and the placenta.[2] The total gestation period from fertilization to birth is normally about 38 weeks (birth usually occurring 40 weeks after the last menstrual period). The normal process of childbirth takes several hours and has three stages. The first stage starts with a series of involuntary contractions of the muscular walls of the uterus and gradual dilation of the cervix. The active phase of the first stage starts when the cervix is dilated more than about 4 cm in diameter and is when the contractions become stronger and regular. The head (or the buttocks in a breech birth) of the baby is pushed against the cervix, which gradually dilates until is fully dilated at 10 cm diameter. At some time, the amniotic sac bursts and the amniotic fluid escapes (also known as rupture of membranes or breaking the water).[6] In stage two, starting when the cervix is fully dilated, strong contractions of the uterus and active pushing by the mother expels the baby out through the vagina, which during this stage of labour is called a birth canal as this passage contains a baby, and the baby is born with umbilical cord attached.[7] In stage three, which begins after the birth of the baby, further contractions expel the placenta, amniotic sac, and the remaining portion of the umbilical cord usually within a few minutes.[8]

    Enormous changes take place in the newborn’s circulation to enable breathing in air. In the uterus, the unborn baby is dependent on circulation of blood through the placenta for sustenance including gaseous exchange and the unborn baby’s blood bypasses the lungs by flowing through the foramen ovale, which is a hole in the septum dividing the right atrium and left atrium. After birth the umbilical cord is clamped and cut, the baby starts to breathe air, and blood from the right ventricle starts to flow to the lungs for gaseous exchange and oxygenated blood returns to the left atrium, which is pumped into the left ventricle, and then pumped into the main arterial system. As result of these changes, the blood pressure in the left atrium exceeds the pressure in the right atrium, and this pressure difference forces the foramen ovale to close separating the left and right sides of the heart. The umbilical vein, umbilical arteries, ductus venosus and ductus arteriosus are not needed for life in air and in time these vessels become ligaments (embryonic remnants).[9]

    Cattle[edit]

    A cow giving birth

    Birthing in cattle is typical of a larger mammal. A cow goes through three stages of labor during normal delivery of a calf. During stage one, the animal seeks a quiet place away from the rest of the herd. Hormone changes cause soft tissues of the birth canal to relax as the mother’s body prepares for birth. The contractions of the uterus are not obvious externally, but the cow may be restless. She may appear agitated, alternating between standing and lying down, with her tail slightly raised and her back arched. The fetus is pushed toward the birth canal by each contraction and the cow’s cervix gradually begins to dilate. Stage one may last several hours, and ends when the cervix is fully dilated. Stage two can be seen to be underway when there is external protrusion of the amniotic sac through the vulva, closely followed by the appearance of the calf’s front hooves and head in a front presentation (or occasionally the calf’s tail and rear end in a posterior presentation).[10] During the second stage, the cow will usually lie down on her side to push and the calf progresses through the birth canal. The complete delivery of the calf (or calves in a multiple birth) signifies the end of stage two. The cow scrambles to her feet (if lying down at this stage), turns round and starts vigorously licking the calf. The calf takes its first few breaths and within minutes is struggling to rise to its feet. The third and final stage of labor is the delivery of the placenta, which is usually expelled within a few hours and is often eaten by the normally herbivorous cow.[10][11]

    Dogs[edit]

    Further information: Canine reproduction § Gestation and litters

    Birth is termed whelping in dogs.[12] Among dogs, as whelping approaches, contractions become more frequent. Labour in the bitch can be divided into 3 stages. The first stage is when the cervix dilates, this causes discomfort and restlessness in the bitch. Common signs of this stage are panting, fasting, and/or vomiting. This may last up to 12hrs.[12] Stage two is the passage of the offspring.[12] The amniotic sac looking like a glistening grey balloon, with a puppy inside, is propelled through the vulva. After further contractions, the sac is expelled and the bitch breaks the membranes releasing clear fluid and exposing the puppy. The mother chews at the umbilical cord and licks the puppy vigorously, which stimulates it to breathe. If the puppy has not taken its first breath within about six minutes, it is likely to die. Further puppies follow in a similar way one by one usually with less straining than the first usually at 15-60min intervals. If a pup has not been passed in 2 hrs a veterinarian should be contacted.[12] Stage three is the passing of the placentas. This often occurs in conjunction with stage two with the passing of each offspring.[12] The mother will then usually eat the afterbirth.[13] This is an adaption to keep the den clean and prevent detection of predators.[12]

    Marsupials[edit]

    See also: Marsupial § Reproductive system, and Marsupial § Early development

    A kangaroo joey firmly attached to a nipple inside the pouch

    An infant marsupial is born in a very immature state. The gestation period is usually shorter than the intervals between oestrus periods. The first sign that a birth is imminent is the mother cleaning out her pouch. When it is born, the infant is pink, blind, furless and a few centimetres long. It has nostrils in order to breathe and forelegs to cling onto its mother’s hairs but its hind legs are undeveloped. It crawls through its mother’s fur and makes its way into the pouch. Here it fixes onto a teat which swells inside its mouth. It stays attached to the teat for several months until it is sufficiently developed to emerge.[14] Joeys are born with “oral shields”; in species without pouches or with rudimentary pouches these are more developed than in forms with well-developed pouches, implying a role in maintaining the young attached to the mother’s nipple.[15]

    Other animals[edit]

    Many reptiles and the vast majority of invertebrates, most fish, amphibians and all birds are oviparous, that is, they lay eggs with little or no embryonic development taking place within the mother. In aquatic organisms, fertilization is nearly always external with sperm and eggs being liberated into the water (an exception is sharks and rays, which have internal fertilization[16]). Millions of eggs may be produced with no further parental involvement, in the expectation that a small number may survive to become mature individuals. Terrestrial invertebrates may also produce large numbers of eggs, a few of which may avoid predation and carry on the species. Some fish, reptiles and amphibians have adopted a different strategy and invest their effort in producing a small number of young at a more advanced stage which are more likely to survive to adulthood. Birds care for their young in the nest and provide for their needs after hatching and it is perhaps unsurprising that internal development does not occur in birds, given their need to fly.[17]

    Ovoviviparity is a mode of reproduction in which embryos develop inside eggs that remain in the mother’s body until they are ready to hatch. Ovoviviparous animals are similar to viviparous species in that there is internal fertilization and the young are born in an advanced state, but differ in that there is no placental connection and the unborn young are nourished by egg yolk. The mother’s body provides gas exchange (respiration), but that is largely necessary for oviparous animals as well.[17] In many sharks the eggs hatch in the oviduct within the mother’s body and the embryos are nourished by the egg’s yolk and fluids secreted by glands in the walls of the oviduct.[18] The Lamniforme sharks practice oophagy, where the first embryos to hatch consume the remaining eggs and sand tiger shark pups cannibalistically consume neighbouring embryos. The requiem sharks maintain a placental link to the developing young, this practice is known as viviparity. This is more analogous to mammalian gestation than to that of other fishes. In all these cases, the young are born alive and fully functional.[19] The majority of caecilians are ovoviviparous and give birth to already developed offspring. When the young have finished their yolk sacs they feed on nutrients secreted by cells lining the oviduct and even the cells themselves which they eat with specialist scraping teeth.[20] The Alpine salamander (Salamandra atra) and several species of Tanzanian toad in the genus Nectophrynoides are ovoviviparous, developing through the larval stage inside the mother’s oviduct and eventually emerging as fully formed juveniles.[21]

    A more developed form of viviparity called placental viviparity is adopted by some species of scorpions[22] and cockroaches,[23] certain genera of sharks, snakes and velvet worms. In these, the developing embryo is nourished by some form of placental structure. The earliest known placenta was found recently in a group of extinct fishes called placoderms, which are ancestral to mammals. A fossil from Australia’s Gogo Formation, laid down in the Devonian period, 380 million years ago, was found with an embryo inside it connected by an umbilical cord to a yolk sac. The find confirmed the hypothesis that a sub-group of placoderms, called ptyctodontids, fertilized their eggs internally. Some fishes that fertilize their eggs internally also give birth to live young, as seen here. This discovery moved our knowledge of live birth back 200 million years.[24] The fossil of another genus was found with three embryos in the same position.[25] Placoderms are a sister group of the ancestor of all living jawed fishes (Gnathostomata), including both chondrichthyians, the sharks & rays, and Osteichthyes, the bony fishes.

    Among lizards, the viviparous lizard Zootoca vivipara, slow worms and many species of skink are viviparous, giving birth to live young. Some are ovoviviparous but others such as members of the genera Tiliqua and Corucia, give birth to live young that develop internally, deriving their nourishment from a mammal-like placenta attached to the inside of the mother’s uterus. In a recently described example, an African species, Trachylepis ivensi, has developed a purely reptilian placenta directly comparable in structure and function to a mammalian placenta.[26] Vivipary is rare in snakes, but boas and vipers are viviparous, giving birth to live young.

    Female aphid giving birth

    The majority of insects lay eggs but a very few give birth to offspring that are miniature versions of the adult.[17] The aphid has a complex life cycle and during the summer months is able to multiply with great rapidity. Its reproduction is typically parthenogenetic and viviparous and females produce unfertilized eggs which they retain within their bodies.[27] The embryos develop within their mothers’ ovarioles and the offspring are clones of their mothers. Female nymphs are born which grow rapidly and soon produce more female offspring themselves.[28] In some instances, the newborn nymphs already have developing embryos inside them.[17]

    See also[edit]

    • Animal sexual behaviour
    • Breeding season
    • Dystocia
    • Foaling (horses)
    • Gestation
    • Kegel exercises
    • Lambing (sheep)
    • Mating system
    • Odon device
    • Reproduction
    • Reproductive system
    • Perineal massage
    • Episiotomy
    • Caesarean section
    • Forceps delivery
    • Ventouse

    References[edit]

  • ^ “birth”. OED Online. June 2013. Oxford University Press. Entry 19395 (accessed 30 August 2013).
  • ^ a b Dorit, R. L.; Walker, W. F.; Barnes, R. D. (1991). Zoology. Saunders College Publishing. pp. 526–527. ISBN 978-0-03-030504-7. 
  • ^ Mark Simmonds, Whales and Dolphins of the World, New Holland Publishers (2007), Ch. 1, p. 32 ISBN 1845378202.
  • ^ Crockett, Gary (2011). “Humpback Whale Calves”. Humpback whales Australia. Retrieved 2013-08-28. 
  • ^ “Trunk Twins : Elephant Twins Born in Tarangire | Asilia Africa”. Asilia Africa. 2018-04-06. Retrieved 2018-04-06. 
  • ^ NICE (2007). Section 1.6, Normal labour: first stage
  • ^ NICE (2007). Section 1.7, Normal labour: second stage
  • ^ NICE (2007). Section 1.8, Normal labour: third stage
  • ^ Houston, Rob (editor); Lea, Maxine (art editor) (2007). The Human Body Book. Dorling Kindersley. p. 215. ISBN 978-1-8561-3007-3. CS1 maint: Extra text: authors list (link)
  • ^ a b “Calving”. Alberta: Agriculture and Rural Development. 2000-02-01. Retrieved 2013-08-28. 
  • ^ “Calving Management in Dairy Herds: Timing of Intervention and Stillbirth” (PDF). The Ohio State University College of Veterinary Medicine Extension. 2012. Retrieved 2013-12-17. 
  • ^ a b c d e f Kustritz, M. (2005). “Reproductive behaviour of small animals”. Theriogenology. 64 (3): 734–746. doi:10.1016/j.theriogenology.2005.05.022. 
  • ^ Dunn, T.J. “Whelping: New Puppies On The Way!”. Puppy Center. Pet MD. Retrieved 2013-08-28. 
  • ^ “Reproduction and development”. Thylacine Museum. Retrieved 2013-08-28. 
  • ^ Yvette Schneider Nanette (Aug 2011). “The development of the olfactory organs in newly hatched monotremes and neonate marsupials”. J. Anat. 219 (2): 229–242. doi:10.1111/j.1469-7580.2011.01393.x. PMC 3162242 . 
  • ^ Sea World, Sharks & Rays; accessed 2013.09.09.
  • ^ a b c d Attenborough, David (1990). The Trials of Life. pp. 26–30. ISBN 9780002199124. 
  • ^ Adams, Kye R.; Fetterplace, Lachlan C.; Davis, Andrew R.; Taylor, Matthew D.; Knott, Nathan A. (January 2018). “Sharks, rays and abortion: The prevalence of capture-induced parturition in elasmobranchs”. Biological Conservation. 217: 11–27. doi:10.1016/j.biocon.2017.10.010. 
  • ^ “Birth and care of young”. Animals: Sharks and rays. Busch Entertainment Corporation. Archived from the original on August 3, 2013. Retrieved 2013-08-28. 
  • ^ Stebbins, Robert C.; Cohen, Nathan W. (1995). A Natural History of Amphibians. Princeton University Press. pp. 172–173. ISBN 978-0-691-03281-8. 
  • ^ Stebbins, Robert C.; Cohen, Nathan W. (1995). A Natural History of Amphibians. Princeton University Press. p. 204. ISBN 978-0-691-03281-8. 
  • ^ Capinera, John L., Encyclopedia of entomology. Springer Reference, 2008, p. 3311.
  • ^ Costa, James T., The Other Insect Societies. Belknap Press, 2006, p. 151.
  • ^ Dennis, Carina (2008-05-28). “Nature News: The oldest pregnant mum: Devonian fossilized fish contains an embryo”. Nature. 453 (7195): 575. Bibcode:2008Natur.453..575D. doi:10.1038/453575a. 
  • ^ Long, John A.; Trinastic, Kate; Young, Gavin C.; Senden, Tim (2008-05-28). “Live birth in the Devonian period”. Nature. 453 (7195): 650–652. Bibcode:2008Natur.453..650L. doi:10.1038/nature06966. PMID 18509443. 
  • ^ Blackburn DG, Flemming AF (2012). “Invasive implantation and intimate placental associations in a placentotrophic African lizard, Trachylepis ivensi (scincidae)”. J. Morphol. 273 (2): 137–59. doi:10.1002/jmor.11011. PMID 21956253. 
  • ^ Blackman, Roger L (1979). “Stability and variation in aphid clonal lineages”. Biological Journal of the Linnean Society. 11 (3): 259–277. doi:10.1111/j.1095-8312.1979.tb00038.x. ISSN 1095-8312. 
  • ^ Conrad, Jim (2011-12-10). “The aphid life cycle”. The Backyard Nature Website. Retrieved 2013-08-31. 
  • Cited texts[edit]

    • “Intrapartum care: Care of healthy women and their babies during childbirth”. NICE. September 2007. Archived from the original on 2014-04-26. 


    Several birth

    “Triplets” redirects here. For other uses, see Triplet.

    Identical triplet brothers at graduation. Identical triplets are extremely rare.

    A multiple birth is the culmination of one multiple pregnancy, wherein the mother delivers two or more offspring. A term most applicable to placental species, multiple births occur in most kinds of mammals, with varying frequencies. Such births are often named according to the number of offspring, as in twins and triplets. In non-humans, the whole group may also be referred to as a litter, and multiple births may be more common than single births. Multiple births in humans are the exception, and can be exceptionally rare in the largest mammals.

    Each single fertilized egg (zygote) may produce a single embryo, or it may split into two or more embryos, each carrying the same genetic material. Fetuses resulting from different zygotes are called fraternal and share only 50% of their genetic material, as ordinary full siblings from separate births do. Fetuses resulting from the same zygote share 100% of their genetic material, and are hence called identical and are always of the same sex (except in cases of Turner syndrome).

    A multiple pregnancy may be the result of the fertilization of a single egg that then splits to create identical fetuses, or it may be the result of the fertilization of multiple eggs that create fraternal fetuses, or it may be a combination of these two. A multiple pregnancy from a single zygote is called monozygotic, from two zygotes is called dizygotic, or from two or more zygotes is called polyzygotic.

    Similarly, the siblings themselves from a multiple birth may be referred to as monozygotic if they are identical, or as polyzygotic if they are fraternal.

    Contents

    • 1 Terminology
    • 2 Human multiple births
      • 2.1 Twins
      • 2.2 Triplets
      • 2.3 Quadruplets
      • 2.4 Quintuplets
      • 2.5 Sextuplets
      • 2.6 Very high-order multiple births
    • 3 Causes and frequency
    • 4 Risks
      • 4.1 Premature birth and low birth weight
      • 4.2 Cerebral palsy
      • 4.3 Incomplete separation
      • 4.4 Mortality rate (stillbirth)
      • 4.5 Prevention in IVF
    • 5 Management
      • 5.1 Selective reduction
      • 5.2 Care in pregnancy
      • 5.3 Nutrition
      • 5.4 Cesarean section or vaginal delivery
      • 5.5 Neonatal intensive care
    • 6 Society and culture
      • 6.1 Insurance coverage
      • 6.2 Cultural aspects
    • 7 See also
    • 8 References
    • 9 External links

    Terminology[edit]

    Fraternal twins at two weeks old. The technical term for “fraternal” is “polyzygotic”.

    Fraternal twin sisters taking a nap. Nonidentical twins, the most common kind of multiple birth among humans, occur in about 1 out of every 80 pregnancies.

    Terms used for multiple births or the genetic relationships of their offspring:

    • Monozygotic – multiple (typically two) fetuses produced by the splitting of a single zygote
    • Dizygotic – multiple (typically two) fetuses produced by two zygotes
    • Trizygotic – three or more fetuses produced by three zygotes
    • Polyzygotic – multiple fetuses produced by two or more zygotes

    Terms used for the number of offspring in a multiple birth:

    • Two offspring – twins
    • Three offspring – triplets
    • Four offspring – quadruplets
    • Five offspring – quintuplets
    • Six offspring – sextuplets
    • Seven offspring – septuplets
    • Eight offspring – octuplets
    • Nine offspring – nonuplets
    • Ten offspring – decuplets

    See List of Multiple Births

    Human multiple births[edit]

    In humans, the average length of pregnancy (two weeks fewer than gestation) is 38 weeks with a single fetus. This average decreases for each additional fetus: to thirty-six weeks for twin births, thirty-two weeks for triplets, and thirty weeks for quadruplets. With the decreasing gestation time, the risks from immaturity at birth and subsequent viability increase with the size of the sibling group. Only as of the twentieth century have more than four all survived infancy.

    Recent history has also seen increasing numbers of multiple births. In the United States, it has been estimated that by 2011, 36% of twin births and 78% of triplet and higher-order births resulted from conception by assisted reproductive technology.[1]

    Twins[edit]

    Main article: Twin

    Twins are by far the most common form of multiple births in humans. The U.S. Centers for Disease Control and Prevention report more than 132,000 sets of twins out of 3.9 million births of all kinds each year, about 3.4%, or 1 in 30.[2]

    Triplets[edit]

    Identical triplets like these three sisters occur when a single fertilized egg splits in two and then one of the resulting two eggs splits again.

    Play media

    Monoamniotic triplets as seen on ultrasound[3]

    Identical triplets come from a monozygotic pregnancy, three fetuses from one egg. The most common set, strictly fraternal triplets, comes from a polyzygotic pregnancy of three eggs. Between these types, triplets that include an identical (monozygotic) pair of siblings plus a fraternal sibling are the result of a dizygotic pregnancy, where one zygote divides into two fetuses and the other doesn’t.

    Triplets are far less common than twins, according to the U.S. Centers for Disease Control and Prevention, accounting for only about 4300 sets in 3.9 million births, just a little more than 0.1%, or 1 in 1000.[2] According to the American Society of Reproductive Medicine, only about 10% of these are identical triplets: about 1 in ten thousand.[2] Nevertheless, only 4 sets of identical triplets were reported in the U.S. during 2015, about one in a million.[2] According to Victor Khouzami, Chairman of Obstetrics at Greater Baltimore Medical Center, “No one really knows the incidence”.[2]

    Identical triplets or quadruplets are very rare and result when the original fertilized egg splits and then one of the resultant cells splits again (for triplets) or, even more rarely, a further split occurs (for quadruplets). The odds of having identical triplets is unclear. News articles and other non-scientific organizations give odds from one in 60,000 to one in 200 million pregnancies.[2][4][5][6][7][8]

    Quadruplets[edit]

    Quadruplets are much rarer than twins or triplets. As of 2007, there were approximately 3500 sets recorded worldwide. Quadruplet births are becoming increasingly common due to fertility treatments. There are around 70 sets of all-identical quadruplets worldwide. Many sets of quadruplets contain a mixture of identical and fraternal siblings, such as three identical and one fraternal, two identical and two fraternal, or two pairs of identicals. One famous set of identical quadruplets was the Genain quadruplets, all of whom developed schizophrenia. Quadruplets are sometimes referred to as “quads” in Britain.[9]

    Quintuplets[edit]

    The Canadian Dionne sisters, seen in this 1947 photograph, were the first quintuplets known to survive infancy.

    Quintuplets occur naturally in 1 in 55,000,000 births.[10] The first quintuplets known to survive infancy were the all-female Canadian Dionne Quintuplets, born in 1934. Quintuplets are sometimes referred to as “quins” in the UK and “quints” in North America.[11]

    Sextuplets[edit]

    Born in Liverpool, England on 18 November 1983, the Walton sextuplets were the world’s first all-female surviving sextuplets, and the world’s fourth known set of surviving sextuplets. Another well-known set of sextuplets is the Gosselin sextuplets, born May 10, 2004 in Hershey, Pennsylvania.[12] Reality television shows called Jon & Kate Plus 8 and later Kate Plus 8 have chronicled the lives of these sextuplets.

    Very high-order multiple births[edit]

    In 1997, the McCaughey septuplets were born in Carlisle, Iowa. Multiple births of as many as eight babies have been born alive, the first set on record to the Chukwu family in Texas in 1998; one died and seven survived. In 2009, a second set, the Suleman octuplets, were born in Bellflower, California.[13][14] The most recent report that all were still alive shortly before their fifth birthday.[15]

    There have been a few sets of nonuplets (nine) in which a few babies were born alive, though none lived longer than a few days. There have been cases of human pregnancies that started out with ten, eleven, twelve or fifteen fetuses, but no instances of live births. The pregnancies of the 10, 11 and 15 fetuses have all resulted from fertility medications and assisted reproductive technology (ART). However, there has been one documented case when 12 fetuses were conceived naturally.[16][not in citation given]

    Causes and frequency[edit]

    The frequency of N multiple births from natural pregnancies has been given as approximately 1:89N-1 (Hellin’s law) and as about 1:80N-1.[17] This gives:

    • 1:89 (= 1.1%) or 1:80 (= 1.25%) for twins
    • 1:892 (= 1:7921, about 0.013%) or 1:802 (= 1:6400) for triplets
    • 1:893 (= approx. 0.000142%, less than 1:700,000) or 1:803 for quadruplets

    North American dizygotic twinning occurs about once in 83 conceptions, and triplets about once in 8000 conceptions. US figures for 2010 were:[18][19]

    • Twins, 132,562, 3.31%
    • Triplets, 5,503, 0.14%
    • Quadruplets, 313, 0.0078%
    • Quintuplets and more, 37, 0.00092%

    Human multiple births can occur either naturally (the woman ovulates multiple eggs or the fertilized egg splits into two) or as the result of infertility treatments such as IVF (several embryos are often transferred to compensate for lower quality) or fertility drugs (which can cause multiple eggs to mature in one ovulatory cycle).

    For reasons that are not yet known, the older a woman is, the more likely she is to have a multiple birth naturally. It is theorized that this is due to the higher level of follicle-stimulating hormone that older women sometimes have as their ovaries respond more slowly to FSH stimulation.[20]

    The number of multiple births has increased over the last decade. For example, in Canada between 1979 and 1999, the number of multiple birth babies increased 35%. Before the advent of ovulation-stimulating drugs, triplets were quite rare (approximately 1 in 8000 births) and higher-order births much rarer still.[citation needed] Much of the increase can probably be attributed to the impact of fertility treatments, such as in-vitro fertilization. Younger patients who undergo treatment with fertility medication containing artificial FSH, followed by intrauterine insemination, are particularly at risk for multiple births of higher order.

    The Gosselin sextuplets with their parents and sisters, cover of KoreAm, May 2008

    Certain factors appear to increase the likelihood that a woman will naturally conceive multiples. These include:

    • mother’s age: women over 35 are more likely to have multiples than younger women[21]
    • mother’s use of fertility drugs: approximately 35% of pregnancies arising through the use of fertility treatments such as IVF involve more than one child

    The increasing use of fertility drugs and consequent increased rate of multiple births has made the phenomenon of multiples more frequent and hence more visible. In 2004 the birth of sextuplets, six children, to Pennsylvania couple Kate and Jon Gosselin helped them to launch their television series, originally Jon & Kate Plus 8 and (following their divorce) Kate Plus 8, which became the highest-rated show on the TLC network.

    Risks[edit]

    Premature birth and low birth weight[edit]

    Babies born from multiple-birth pregnancies are much more likely to result in premature birth than those from single pregnancies. 51% of twins and 91% of triplets are born preterm, compared to 9.4% in singletons.[22] 14% of twins and 41% of triplets are even born very preterm, compared to 1.7% in singletons.[22]

    At present, there is no way to stop twins being born early.[23] In women with single pregnancies drugs called betamimetics can relax the muscles of the uterus and delay birth.[24] Giving betamimetics can give more time to give steroids, for the baby’s lung development, or to transfer the mother to a hospital with a special care unit.[24]

    However, there is not enough evidence to say whether or not women with twin pregnancies should be given oral betamimetics to reduce the risk of preterm birth.[23] In some studies betamimetics have reduced the rate of preterm labour in twin pregnancies however the studies are too small to draw any solid conclusions.[23] Likewise, putting a stitch in the neck of the womb (a cervical suture) to prevent premature birth has not been shown to work in women carrying more than one baby due to the small sample sizes in the studies.[25]

    The preterm births also result in multiples tending to have a lower birth weight compared to singletons.

    Some evidence[who?] indicates that only 1.10% of singletons are born with a very low birth weight and 10.12% twins and 31.88% triplets were found to be born with very low birth weight. This study[who?] was conducted by looking at the statistics from the U.S. Natality Files (5).

    Among the exceptions are the Kupresak triplets of Mississauga, Ontario, Canada; their combined weight at birth in 2008, of 17 lbs, 2.7 ounces, set a world record.[26]

    Cerebral palsy[edit]

    Cerebral palsy is more common among multiple births than single births, being 2.3 per 1,000 survivors in singletons, 13 in twins, and 45 in triplets in North West England.[27] This is likely a side effect of premature birth and low birth weight.

    Incomplete separation[edit]

    Further information: Twin § Degree of separation

    Multiples may be monochorionic, sharing the same chorion, with resultant risk of twin-to-twin transfusion syndrome. Monochorionic multiples may even be monoamniotic, sharing the same amniotic sac, resulting in risk of umbilical cord compression and nuchal cord. In very rare cases, there may be conjoined twins, possibly impairing function of internal organs.

    Mortality rate (stillbirth)[edit]

    Multiples are also known to have a higher mortality rate. It is more common for multiple births to be stillborn, while for singletons the risk is not as high. A literary review on multiple pregnancies shows a study done on one set each of septuplets and octuplets, two sets of sextuplets, 8 sets of quintuplets, 17 sets of quadruplets, and 228 sets of triplets. By doing this study, Hammond found that the mean gestational age (how many weeks when birthed) at birth was 33.4 weeks for triplets and 31 weeks for quadruplets. This shows that stillbirth happens usually 3–5 weeks before the woman reaches full term and also that for sextuplets or higher it almost always ends in death of the fetuses.[28] Though multiples are at a greater risk of being stillborn, there is inconclusive evidence whether the actual mortality rate is higher in multiples than in singletons.

    Prevention in IVF[edit]

    Today many multiple pregnancies are the result of in vitro fertilisation (IVF). In a study in 1997 of 2,173 embryo transfers performed as part of in vitro fertilisation (IVF), 34% were successfully delivered pregnancies.[29] The overall multiple pregnancy rate was 31.3% (24.7% twins, 5.8% triplets, and .08% quadruplets).[29] Because IVFs are producing more multiples, a number of efforts are being made to reduce the risk of multiple births- specifically triplets or more. Medical practitioners are doing this by limiting the number of embryos per embryo transfer to one or two. That way, the risks for the mother and fetuses are decreased.

    The appropriate number of embryos to be transferred depends on the age of the woman, whether it is the first, second or third full IVF cycle attempt and whether there are top-quality embryos available. According to a guideline from The National Institute for Health and Care Excellence (NICE) in 2013, the number of embryos transferred in a cycle should be chosen as in following table:[30]

    Also, it is recommended to use single embryo transfer in all situations if a top-quality blastocyst is available.[30]

    Management[edit]

    Bed rest has not been found to change outcomes and therefore is not generally recommended outside of a research study.[31]

    Selective reduction[edit]

    Main article: Selective reduction

    Selective reduction is the termination of one or more, but not all, of the fetuses in a multiple pregnancy. This is often done in pregnancies with multiple gestations to increase the likelihood that one child may live a healthy life. Armour[32] reported a loss rate of 5.4% in a review of 1,000 cases of selective reduction. Fifteen percent of the losses occurred within 4 weeks of the procedures and more than 50% occurred after 8 weeks. This suggests that the reduction was successful at reducing the embryos from multiple gestations to single.

    Though selective reduction seems to be effective, mothers of multiples who undergo this procedure are at a higher risk of miscarrying compared to that of an unreduced multiple pregnancy. A study done by looking at 158 pregnant women who underwent selective reduction from higher order multiples to twins showed that the mother had a 10.6% chance of miscarriage. Mothers of twin pregnancies without reduction only had a 9.5% chance of miscarriage. A study by Antsaklis[33] showed a small increase in mortality for reduced twin pregnancies versus unreduced twin pregnancies.

    However, there is a lack of good quality research on the risks and benefits of selective reduction procedures.[34] Many parents often find the suggestion of selective termination upsetting particularly if the pregnancy is a result of IVF or they have had difficulty getting pregnant in the past. Background, religious or personal beliefs can all play a part in effecting whether parents want to go through with the procedure and could be the reason why research in this area is scarce.[34]

    Competition among fertility clinics does not appear to increase rates of multiple births from fertility treatment by promoting more aggressive embryo transfer decisions.[35]

    Care in pregnancy[edit]

    Women with a multiple pregnancy are usually seen more regularly by midwives or doctors than those with singleton pregnancies because of the higher risks of complications.[36] However, there is currently no evidence to suggest that specialised antenatal services produce better outcomes for mother or babies than ‘normal’ antenatal care. [37]

    Nutrition[edit]

    As preterm birth is such a risk for women with multiple pregnancies, it has been suggested that these women should be encouraged to follow a high-calorie diet to increase the birth weights of the babies. Evidence around this subject is not yet good enough to advise women to do this because the long term effects of the high-calorie diets on the mother are not known.[38]

    Cesarean section or vaginal delivery[edit]

    A study in 2013 involving 106 participating centers in 25 countries came to the conclusion that, in a twin pregnancy of a gestational age between 32 weeks 0 days and 38 weeks 6 days, and the first twin is in cephalic presentation, planned Cesarean section does not significantly decrease or increase the risk of fetal or neonatal death or serious neonatal disability, as compared with planned vaginal delivery.[39] In this study, 44% of the women planned for vaginal delivery still ended up having Cesarean section for unplanned reasons such as pregnancy complications. In comparison, it has been estimated that 75% of twin pregnancies in the United States were delivered by Cesarean section in 2008.[40] Also in comparison, the rate of Cesarean section for all pregnancies in the general population varies between 40% and 14%.[41]

    Fetal position (the way the babies are lying in the womb) usually determines if they are delivered by caesarean section or vaginally. A review of good quality research on this subject found that if the twin that will be born first (i.e. is lowest in the womb) is head down there is no good evidence that caesarean section will be safer than a vaginal birth for the mother or babies.[42]

    Monoamniotic twins (twins that form after the splitting of a fertilised egg and share the same amniotic fluid sac) are at more risk of complications than twins that have their own sacs. There is also insufficient evidence around whether to deliver the babies early by caesarean section or to wait for labour to start naturally while running checks on the babies’ wellbeing.[43] The birth of this type of twins should therefore be decided with the mother and her family and should take into account the need for good neonatal care services.[44]

    Cesarean delivery is needed when first twin is in non cephalic presentation or when it is a monoamniotic twin pregnancy.

    Neonatal intensive care[edit]

    Multiple-birth infants are usually admitted to neonatal intensive care immediately after being born. The records for all the triplet pregnancies managed and delivered from 1992-1996 were looked over to see what the neonatal statistics were. Kaufman[45] found from reviewing these files that during a five-year period, 55 triplet pregnancies, which is 165 babies, were delivered. Of the 165 babies 149 were admitted to neonatal intensive care after the delivery.

    Society and culture[edit]

    A women bearing 9 or 11 children, Prodigiorum ac ostentorum chronicon, 1557, by Conrad Lycosthenes

    Insurance coverage[edit]

    A study by the U.S. Agency for Healthcare Research and Quality found that, in 2011, pregnant women covered by private insurance in the United States were older and more likely to have multiple gestation than women covered by Medicaid.[46]

    Cultural aspects[edit]

    Certain cultures consider multiple births a portent of either good or evil.[47]

    Mayan culture saw twins as a blessing, and was fascinated by the idea of two bodies looking alike. The Mayans used to believe that twins were one soul that had fragmented.[citation needed]

    In Ancient Rome, the legend of the twin brothers who founded the city (Romulus and Remus) made the birth of twin boys a blessing, while twin girls were seen as an unlucky burden, since both would have to be provided with an expensive dowry at about the same time.

    Beatrix with her seven swan-children, in the Knight of the Swan romance (Talbot Shrewsbury Book)

    In Greek mythology, fraternal twins Castor and Polydeuces, and Heracles and Iphicles, are sons of two different fathers. One of the twins (Polydeuces, Heracles) is the illegitimate son of the god Zeus; his brother is the son of their mother’s mortal husband. A similar pair of twin sisters are Helen (of Troy) and Clytemnestra (who are also sisters of Castor and Polydeuces). The theme occurs in other mythologies as well, and is called superfecundation.

    In certain medieval European chivalric romances, such as Marie de France’s Le Fresne, a woman cites a multiple birth (often to a lower-class woman) as proof of adultery on her part; while this may reflect a widespread belief, it is invariably treated as malicious slander, to be justly punished by the accuser having a multiple birth of her own, and the events of the romance are triggered by her attempt to hide one or more of the children.[48] A similar effect occurs in the Knight of the Swan romance, in the Beatrix variants of the Swan-Children; her taunt is punished by giving birth to seven children at once, and her wicked mother-in-law returns her taunt before exposing the children.[49]

    See also[edit]

    • Biological reproduction
    • Conjoined twins
    • The Loud House a 2016 animated series, the character Rita Loud was the mother of eleven children.
    • Half a Dozen Babies a 1999 drama film, about the 1993 born Dilley sextuplets.
    • List of multiple births
    • List of twins
    • Only child
    • Superfecundation (multiple pregnancy resulting from separate sexual intercourses)
    • Twin
    • Feodor Vassilyev

    References[edit]

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  • ^ “UOTW #19 – Ultrasound of the Week”. Ultrasound of the Week. 23 September 2014. Retrieved 27 May 2017. 
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  • ^ Fierro, Pamela Prindle (December 15, 2014). “Identical Triplets”. About.com. Retrieved 15 January 2015. 
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  • ^ Octuplets born in Bellflower, LA Times
  • ^ 8 facts about ‘Octomom’ Nadya Suleman
  • ^ Facts About Multiples
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  • ^ McCall, CA; Grimes, DA; Lyerly, AD (June 2013). “”Therapeutic” bed rest in pregnancy: unethical and unsupported by data”. Obstetrics and gynecology. 121 (6): 1305–8. doi:10.1097/aog.0b013e318293f12f. PMID 23812466. 
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  • ^ Women can choose Caesarean birth – BBC article by James Gallagher. 2011.
  • ^ Hofmeyr, GJ; Barrett, JF; Crowther, CA (19 December 2015). “Planned caesarean section for women with a twin pregnancy”. The Cochrane Database of Systematic Reviews. 12: CD006553. doi:10.1002/14651858.CD006553.pub3. PMC 4110647 . PMID 26684389. 
  • ^ Shub, A; Walker, SP (23 April 2015). “Planned early delivery versus expectant management for monoamniotic twins”. The Cochrane Database of Systematic Reviews. 4: CD008820. doi:10.1002/14651858.CD008820.pub2. PMID 25906204. 
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  • ^ Kaufman GE, Malone FD, Harvey-Wilkes KB, Chelmow D, Penzias AS, D’Alton ME (1998). “Neonatal morbidity and mortality associated with triplet pregnancy”. Obstet Gynecol. 91 (3): 342–8. doi:10.1016/s0029-7844(97)00686-8. PMID 9491857. 
  • ^ Moore JE, Witt WP, Elixhauser A (April 2014). “Complicating Conditions Associate With Childbirth, by Delivery Method and Payer, 2011”. HCUP Statistical Brief #173. Rockville, MD: Agency for Healthcare Research and Quality. 
  • ^ “Korea’s ‘lucky’ triplets seized”. Herald Sun. Fairfax. 2003-03-30. 
  • ^ Laura A. Hibbard, Medieval Romance in England p295, 244 New York Burt Franklin,1963
  • ^ Laura A. Hibbard, Medieval Romance in England p239, 243 New York Burt Franklin,1963
  • External links[edit]

    • Facts About Multiples
    • HFEA consultation on multiple births after IVF
    • D. L. Ashliman, Multiple Births in Legend and Folklore
    • Twins and Multiple Births Association

    Childbirth

    Postpartum

    Obstetric history

    • Gravidity
    • Parity
    • TPAL


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    Changed at birth

    Switched at birth may refer to:

    • Babies switched at birth, when newborns’ identities are mixed up at a hospital
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    • Switched at Birth (1999 film), a 1999 television film
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