Uterus didelphys -- or a double womb -- is a pretty rare condition. It affects anywhere from about one in 1,000 to one in 1 million women worldwide, and it sometimes occurs in families. In some cases of double wombs, those two wombs share a set of Fallopian tubes, ovaries, a cervix and a vagina; other times, a girl is born with two of everything -- two wombs, two sets of Fallopian tombs and ovaries, two cervixes and two vaginas. A woman can have a surgical procedure to join her two vaginas into one, but the wombs are typically left separate. The condition usually occurs when the Mullers ducts of a developing fetus never fuse into one uterus, as they're supposed to.
In December 2006 in Britain, three babies were born from two separate wombs inside the same woman. As far as the medical community knows, only about 70 women with uterus didelphys have ever been simultaneously pregnant with one baby in each womb. The chances of it occurring are about 5 million to one. Fewer of those women have carried one or both babies close to term. The chances of a woman with two wombs being pregnant with three babies -- two in one womb, one in the other -- are about 25 million to one. And the chances of all three babies surviving are even slimmer. Twenty-three-year-old Hannah Kersey's three daughters might be the only ones, at least in recorded medical history.
Problems with Double Wombs
The anomaly can cause fertility problems because each uterus is only half the size it would normally be, making it difficult for a baby to fully develop and unlikely that a woman will be able to carry a baby -- let alone two or three -- to full term. There's just not enough room in there. Twenty-five percent of the time, a woman who is pregnant in both wombs simultaneously who makes it to 30 weeks will have to deliver prematurely, usually by cesarian section, before it gets so tight in each womb that the babies can't continue their growth. In most cases, neither womb can stretch enough to accommodate a full-term fetus.
This type of simultaneous pregnancy is quite different having twins from a single womb. In a case of a double pregnancy in two wombs, a woman can deliver the babies days, weeks or months apart since the wombs are totally separate. This can cause problems considering that a scheduled, premature cesarian section is a likely delivery method. Few obstetricians would want a woman to undergo abdominal surgery twice in a month. So if at least one baby has to be delivered via Cesarean section, the doctor will usually recommend delivering both babies at the same time. The result, in that case, is much like having twins -- the woman goes into the hospital and eventually leaves with two babies who are the same age.
According to BBC News, a woman in Brazil with uterus didelphys delivered two healthy babies, one from each womb, in May 2003; and in 2002, the news organization Xinhua reported on a similar case in China. With advances in medical technology, the odds of successfully delivering babies from simultaneous pregnancies in two wombs may be getting a lot better.
Ms. Kersey's three daughters were delivered seven weeks early by Cesarean section and spent two months in the hospital finishing their development. In December 2006, all three went home in good health with their parents.
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