Objective: To determine the relationship between mode of delivery and serious adverse neonatal outcomes in term, singleton, cephalic neonates.
Methods: A 10-year study of 64,555 term neonates reaching the second stage of labor in a single tertiary obstetric unit from 2000 to 2009. Multiple pregnancies, preterm deliveries (before 37 weeks of gestation), and lethal congenital anomalies were excluded. The primary outcome was the rate of peripartum death by mode of delivery. Secondary outcomes were rates of neonatal encephalopathy, intracranial hemorrhage-related mortality, and the relationship between instrument choice and adverse outcomes. Categorical data were compared using the χ test, with odds ratios (ORs) and 95% confidence intervals included when appropriate.
Results: Compared with neonates delivered by second-stage cesarean, there were no differences in the rates of either peripartum neonatal death (OR 0.42; P=.37) or neonatal encephalopathy (OR 1.07; P>.99) after operative vaginal delivery. The rates of neonatal encephalopathy associated with operative vaginal and second-stage cesarean delivery were 4.2 and 3.9 per 1,000 term neonates, respectively. No significant differences in adverse neonatal outcomes were demonstrated between vacuum-assisted and forceps-assisted deliveries, although subanalysis is limited by the small numbers of serious adverse outcomes. The absolute risk of neonatal death secondary to intracranial hemorrhage is 3-4 per 10,000 operative vaginal deliveries for both instruments.
Conclusions: Operative vaginal delivery is associated with similar rates of serious neonatal complications compared with cesarean delivery at full dilatation.
Level of evidence: II.