Prevention of preterm birth.

The preterm birth rate in the USA is nearing 13%. The recent rise has been attributed to increased indicated preterm births and multiple births following artificial conceptions. There are few obstetrical interventions that successfully delay or prevent spontaneous preterm birth or reduce the risk factors leading to indicated preterm birth. On the other hand, there are many strategies that have improved outcomes for those infants who are born preterm. These include the use of corticosteroids for fetal maturation and regionalization of perinatal care for high-risk mothers and their infants. Several interventions, including progesterone use and cerclage, demonstrate promise in reducing spontaneous preterm births. The most pressing need is to better define the populations of pregnant women for whom these and other interventions will effectively reduce preterm birth.