February 16, 2011
Earlier this month, the U.S. Food and Drug Administration approved the use of 17 alpha-hydroxyprogesterone caproate (17P), a drug that reduces the chances of preterm delivery in a group of high risk pregnant women.
A study conducted by NICHD’s Maternal and Fetal Medicine Units Network and published in the New England Journal of Medicine ("Prevention of Recurrent Preterm Delivery by 17 Alpha-Hydroxyprogesterone Caproate,") demonstrated that 17P can reduce the risk of preterm birth. The drug is a synthetic form of the naturally occurring hormone progesterone. Preterm birth increases the risk for death in the first year of life. Preterm infants also are at increased risk for heart problems, blindness, deafness, cerebral palsy and severe learning disabilities.
"The FDA’s approval of 17P provides clinicians with an effective option for reducing the risk of preterm birth in an important category of expectant mothers, those who have delivered prematurely in at least one earlier pregnancy," said NICHD director Alan E. Guttmacher, M.D.
The 2003 study enrolled 463 women 16 to 43 years of age who were pregnant with a single fetus and had given birth prematurely in a previous pregnancy. Roughly two thirds, or 310 women, received 17P, while 153 women received a placebo.
Treatment with 17P reduced the chances of women giving birth early by about one third: 37 percent of the women in the 17P group delivered early, compared with almost 55 percent in the placebo group.
In addition, smaller percentages of women in the 17P group gave birth before the 35th week of pregnancy and before the 32 week of pregnancy than did women receiving the placebo.
The drug is approved only for pregnant women carrying a single fetus who have given birth prematurely in at least one pregnancy. Earlier studies by the NICHD’s Maternal Fetal Medicine Network have shown that the drug is not effective in two other categories of pregnant women: those carrying twins and triplets. A study in the Maternal Fetal Medicine Units Network currently is evaluating its effectiveness in another category of women at risk of preterm birth, those with a shortened uterine cervix who have never given birth before.
FDA granted its approval after completion of another study by the network which followed the children from the original study until they were 48 months old. The researchers found no differences in the health or development of the children in either the progesterone or placebo group.
The FDA’s approval was given under the condition that the drug’s manufacturer conduct additional follow-up studies on the health of children whose mothers received the drug during their pregnancies. According to the FDA, an international study is now in progress to learn if there is also improvement in the outcome of babies born to women given 17P.
The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute’s Web site at http://www.nichd.nih.gov/.
The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.