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

Abstract

To evaluate the association of a new institutional policy limiting elective delivery before 39 weeks of gestation with neonatal outcomes at a large community-based academic center. A retrospective cohort study was conducted to estimate the effect of the policy on neonatal outcomes using a before and after design. All term singleton deliveries 2 years before and 2 years after policy enforcement were included. Clinical data from the electronic hospital obstetric records were used to identify outcomes and relevant covariates. Multivariable logistic regression was used to account for independent effects of changes in characteristics and comorbidities of the women in the cohorts before and after implementation. We identified 12,015 singleton live births before and 12,013 after policy implementation. The overall percentage of deliveries occurring before 39 weeks of gestation fell from 33.1% to 26.4% (P<.001); the greatest difference was for women undergoing repeat cesarean delivery or induction of labor. Admission to the neonatal intensive care unit (NICU) also decreased significantly; before the intervention, there were 1,116 admissions (9.29% of term live births), whereas after, there were 1,027 (8.55% of term live births) and this difference was significant (P=.044). However, an 11% increased odds of birth weight greater than 4,000 g (adjusted odds ratio 1.11; 95% confidence interval [CI] 1.01-1.22) and an increase in stillbirths at 37 and 38 weeks, from 2.5 to 9.1 per 10,000 term pregnancies (relative risk 3.67, 95% CI 1.02-13.15, P=.032), were detected. A policy limiting elective delivery before 39 weeks of gestation was followed by changes in the timing of term deliveries. This was associated with a small reduction in NICU admissions; however, macrosomia and stillbirth increased.