Impacts of embracing 39-week elective induction across an entire labor and delivery unitAJOG Global Reports at a Glance

BACKGROUND: Induction of labor among low-risk, 39-week nulliparas increased significantly in the United States following publication of the outcomes of A Randomized Trial of Induction Versus Expectant Management trial. However, the rates of labor induction and outcomes in non-nulliparous patients and the wider impacts on the labor unit have not been reported widely. OBJECTIVE: This study aimed to compare the induction of labor rates and outcomes before and after liberal implementation of 39-week elective induction at a single center. STUDY DESIGN: This was a retrospective cohort study comparing the delivery characteristics of pregnancies 1 year before and 1 year after adoption of a new 39-week elective induction policy at a single, tertiary-care center. Notably, elective induction was not restricted to nulliparas. We examined all live, singleton, in-born deliveries ≥36 weeks gestation, excluding those with fetal anomalies and prolonged antenatal admission. Deliveries at ≥39 weeks gestation were further subcategorized as being high risk (diabetes mellitus, chronic hypertension, intrauterine growth restriction, history of fetal demise or cholestasis) or low risk, nulliparas vs multiparas, and with or without a previous cesarean delivery. Elective deliveries were those without a maternal, fetal, or obstetrical indication. Primary outcomes included gestational age and indications for delivery, rates of labor induction and elective induction, and time from admission to delivery. Secondary outcomes included the rate of cesarean deliveries, indications for cesarean deliveries, and maternal and newborn morbidities. The outcomes were compared using Wilcoxon rank-sum tests or chi-square tests as appropriate. The odds of cesarean delivery were analyzed using multivariate logistic regression and controlling for relevant confounders. RESULTS: A total of 2672 pre-implementation and 2526 post-implementation deliveries were studied. Among patients at ≥39 weeks gestation, elective delivery increased (pre-implementation, 344/1788 [19.2%] vs post-implementation, 684/1710 [40.0%]; P