Mode of delivery and outcomes in very low-birth-weight infants in the vertex presentation.

We sought to determine the relationship between mode of delivery and neonatal outcomes in infants <1500 g in a vertex presentation. This was a retrospective cohort study of singleton, vertex-presenting infants weighing <1500 g in a level III neonatal intensive care unit between July 1993 and July 2006. Infants were divided into vaginal or cesarean delivery, and outcomes were compared with univariable and multivariable analysis. Of the 937 infants that met inclusion criteria, 402 (42.9%) underwent cesarean delivery. After controlling for potential confounding variables, there was no increased odds of death (odds ratio [OR] = 1.6: 95% confidence interval [CI] 0.8 to 3.0), severe intraventricular hemorrhage (IVH; OR = 1.2: 95% CI 0.7 to 1.2), necrotizing enterocolitis (OR = 0.82: 95% CI 0.35 to 1.9), or sepsis (OR = 0.79: 95% CI 0.44 to 13) in the vaginally delivered group compared with the cesarean group. In a post hoc analysis, this study had 80% power to detect an absolute difference in death or severe IVH of 6% between study groups, with an α of 0.05. In our population of very low-birth-weight infants, there was no association between mode of delivery and neonatal outcomes.