The high number of multiple pregnancies is a concern because women who are expecting more than one baby are at increased risk of certain pregnancy complications, including premature birth.
Multiple Births: Twins, Triplets, and Beyond
Martin, J.A., et al. Births: Final Data for 2006. National Vital Statistics Reports, volume 57, number 7, January 7, 2009. Reddy, U.M., et al. Relationship of Maternal Body Mass Index and Height to Twinning. Obstetrics and Gynecology, volume 105, number 3, March 2005, pages 593-597. Wright, V.C., et al. Assisted Reproductive Technology Surveillance–2005. Morbidity and Mortality Weekly Report, volume 57 (SS05), June 20, 2008. Practice Committee of the Society for Assisted Reproductive Technology and the American Society for Reproductive Medicine. Fertility and Sterility, volume 86, Supplement 5, November 2006, pages S51-52. American Society for Reproductive Medicine. Multiple Pregnancy and Birth: Twins, Triplets, and Higher Order Multiples: A Guide for Patients. Birmingham AL, 2004, accessed 12/16/08. Rossi, C., and D’Addario, V. Laser Therapy and Serial Amnioreduction as Treatment for Twin-Twin Transfusion Syndrome: A Metaanalysis and Review of Literature. American Journal of Obstetrics and Gynecology, volume 198, number 2, February 2008, pages 147-152. Lopriore, E. et al. Risk Factors for Neurodevelopment Impairment in Twin-Twin Transfusion Syndrome Treated With Fetoscopic Laser Surgery. Obstetrics and Gynecology, volume 113, number 2, February 2009, pages 361-366. Senat, M.V., et al. Endoscopic Laser Surgery versus Serial Amnioreduction for Severe Twin-to-Twin Transfusion Syndrome. New England Journal of Medicine, volume 351, number 2, July 8, 2004, pages 136-144. American College of Obstetricians and Gynecologists (ACOG). Multiple Gestation: Complicated Twin, Triplet, and Higher-Order Multifetal Pregnancy. ACOG Practice Bulletin, number 56, October 2004. Institute of Medicine. Weight Gain During Pregnancy: Reexamining the Guidelines. May 2009. New York: National Academy of Sciences, accessed 12/8/09. American College of Obstetricians and Gynecologists (ACOG). Having Twins: Patient Education Pamphlet. ACOG, Washington, DC, 2004, accessed 12/9/08.
When a woman is carrying one baby, it is called a singleton pregnancy. When She is carrying two or more babies it is called multiple births. In the past 2 decades, the rate of multiple births in the United States jumped dramatically. The rate of twin births increased by 70 percent between 1980 and 2004, and the rate of higher-order multiples (triplets or more) increased four-fold between 1980 and 1998 . However, the rapid rise in multiple birth rates may be ending. In 2005 and 2006, the rate of twin births remained stable . The rate of higher-order multiple births has declined 21 percent since its peak in 1998 . Today, more than 3 percent of babies in this country are born in sets of two, three or more; about 95 percent of these multiple births are twins. The high number of multiple pregnancies is a concern because women who are expecting more than one baby are at increased risk of certain pregnancy complications, including premature birth . Premature babies are at risk of serious health problems during the newborn period, as well as lasting disabilities and death. Some of the complications associated with multiple pregnancy can be minimized or prevented when they are diagnosed early. There are a number of steps a pregnant woman and her health care provider can take to help improve the chances that her babies will be born healthy.
About one-third of the increase in multiple pregnancies is due to the fact that more women over age 30 are having babies. Women in this age group are more likely than younger women to conceive multiples. The...