Objective: The purpose of this study was to examine the success rate of labor induction in patients with severe pre-eclampsia delivered at < or = 34 weeks' gestation; to identify factors associated with its success; and to evaluate neonatal outcomes based on induction success or failure.
Methods: We identified pregnancies complicated by severe pre-eclampsia delivered at < or = 34 weeks' at our institution from 1991 to 1998. Women who underwent labor induction and had successful vaginal delivery were compared to those who underwent labor induction, but required Cesarean delivery. Multiple logistic regression analyses were performed to assess factors associated with successful induction and neonatal outcome.
Results: Over the 7-year study period, there were 215 patients meeting the criteria. Sixty-four (29.8%) did not undergo a labor attempt; 69 of 151 (46%) women who underwent labor induction achieved vaginal delivery. Labor induction was successful in 0%, 6.6%, 35.3% and 68.5% of cases at 24-26, 27-28, 29-31 and 32-34 weeks' gestation, respectively. By logistic regression the only factor positively associated with successful induction was gestational age at delivery (p = 0.001), while induction for non-reassuring fetal testing was inversely associated (p = 0.02). Induction attempt, failed induction and delivery mode were not associated with increased neonatal morbidity.
Conclusions: In women with severe pre-eclampsia remote from term, attempted labor induction did not appear to increase neonatal morbidity, but was rarely successful at < 28 weeks.