Risks for Twin Pregnancies
Reported July 4, 2005
(Ivanhoe Newswire) — The number of twins being born today has dramatically increased thanks to assisted conception. Even though multiple pregnancies are more common, they are still risky. In fact, a new study finds uncomplicated twin pregnancies might be even more risky than previously thought. Researchers suggest an early birth could help reduce the risks.
While identical twins are less common than fraternal twins, the number of identical twins has also increased due to induced ovulation and in vitro fertilization. Identical twins can have two amniotic sacs and two placentas, one amniotic sac and one placenta or two amniotic sacs and one placenta. The last type is called diamniotic monochorionic and accounts for two-thirds of all identical twins. Most have no complications.
Researchers from the Institute of Reproductive and Developmental Biology at Imperial College London reviewed the records of 151 diamniotic monochorionic twin cases. The pregnancies had no overt complications, but the researchers found 10 unexpected intrauterine deaths happened in seven of the pregnancies. All of the deaths occurred within two weeks of a normal scan and around the 34th week of pregnancy.
Study authors say despite improved fetal surveillance, the risk for death still exists for twins with no other signs of complications. They suggest fetal death could be eliminated if the babies were delivered at 32 weeks of pregnancy.
Two doctors from Columbia University in New York believe this study highlights a critical question for obstetricians: When is the ideal age to deliver twins who are not having any complications? They say larger studies are needed to better understand the risks in uncomplicated twin pregnancies.
SOURCE: PLoS Medicine, 2005;2:e172