Delivery at 39 Weeks of Gestation: The Time Has Come.

It has long been observed that neonates born between 39 and 40 gestational weeks have the best perinatal outcomes. What has not been known, until recently, is whether these ideal perinatal outcomes would be achieved in neonates whose delivery was brought on intentionally in this window by labor induction. Recent randomized trials and large observational cohorts have answered this question: labor induction, as compared with expectant management, lowers the rate of cesarean delivery (without increasing other adverse maternal outcomes) and improves perinatal outcomes. For those women still pregnant, delivery at 39 weeks of gestation would simultaneously lower the number of cesarean deliveries and reduce the number of stillbirths and neonatal deaths in the United States.