Abstract
Cesarean and induced delivery rates have risen substantially in recent decades and currently account for over one-third and one-fourth of US births, respectively. Initiatives to encourage delaying deliveries until a gestational age of 39 weeks appear to have slowed the increases but have not led to declines. The rates are at historic highs and the consequences of these interventions when not medically necessary have not been systematically explored at the population level. In this study, we used population-level data on births in New Jersey (1997-2011) to document trends in elective deliveries (induced vaginal delivery, cesarean delivery with no labor trial, and cesarean delivery after induction) and estimate logistic and linear regression models of associations between delivery method and neonatal morbidities and cost-related outcomes in low-risk pregnancies. We found that elective deliveries more than doubled during the observation period and were associated with neonatal morbidities and cost-related outcomes even at gestational ages of 39 and 40 weeks. Findings suggest that delaying beyond 39 weeks and avoiding delivery interventions when not medically necessary would improve infant health and reduce health-care costs.