Neonatal Outcomes After Implementation of Guidelines Limiting Elective Delivery Before 39 Weeks of Gestation

Abstract

Either spontaneous or induced delivery before a gestational age of 39 weeks is associated with an increased risk of adverse neonatal outcomes. A significant proportion of induced early-term (37–38 weeks) deliveries are elective and not medically indicated. There has been a national effort to reduce early-term deliveries through implementation of a policy limiting elective delivery before 39 weeks of gestation. After implementation of this policy, several studies reported initial success at shifting the timing of elective delivery at individual hospitals and large regions. However, the effect of this policy on neonatal outcomes has not been fully evaluated. This retrospective cohort study investigated the effectiveness of a new institutional policy limiting elective delivery before 39 weeks of gestation on obstetric practice and neonatal outcomes at a large regional medical center. Outcomes for term singleton deliveries were compared for a period 2 years before and 2 years after implementation of the new policy. Data on medical risk factors for outcomes of interest were obtained from electronic obstetrical records. The study cohort included 12,015 term singleton live births that occurred before implementation and 12,013 after implementation of the policy. The overall percentage of deliveries before 39 weeks of gestation was decreased from 33.1% before to 26.4% after implementation (P < 0.001); the greatest difference was found among women with induced labor and repeat cesarean delivery. After intervention, there was also a significant reduction in the proportion of term live-birth infants admitted to the neonatal intensive care unit: 1116 admissions (9.29%) before and 1027 (8.55%) after (P = 0.044). However, after implementation, there was an 11% increase in the adjusted odds of birth weight >4000 g (odds ratio, 1.11; 95% confidence interval, 1.01–1.22), as well as an increase in stillbirths at 37 and 38 weeks' gestation, from 2.5 to 9.1 per 10,000 term pregnancies (relative risk, 3.67; 95% confidence interval, 1.02–13.15, P = 0.032). These findings demonstrate that implementation of an institutional policy limiting elective delivery before 39 weeks of gestation is effective in changing the timing of term deliveries. However, examination of the data reveals an increase in the rate of macrosomia and stillbirth in contrast to the reduction in neonatal intensive care unit admissions after the intervention.