Perinatal Outcome in 1515 Cases of Prolonged Second Stage of Labour in Nulliparous Women

Objective: To examine perinatal outcomes among nulliparous women with a second stage of labour lasting more than three hours. Methods: We conducted a retrospective review of all nulliparous women over a 14-year period who had a term, live, singleton, cephalic fetus >= 2500 g and who had a second stage of labour lasting at least three hours. Outcome measures included five-minute Apgar score < 7, cord arterial pH < 7.10, admission to the NICU, neonatal seizures, and neonatal death. Rates of serious long-term neurologic morbidity were also analyzed. Outcomes were compared with those of a similar cohort of women who delivered after less than three hours in the second stage. Results: During the study period, 1515 women met the inclusion criteria. The majority of women (67%) delivered vaginally, after up to 10 hours in the second stage of labour. The overall rate of Caesarean section was low (15.7%). The rate of permanent neurologic impairment was 2.6 per 1000 deliveries. Conclusion: Among nulliparous women, 84% were spared a possibly difficult Caesarean section in the second stage of labour or a potentially difficult operative vaginal delivery by allowing a longer second stage. However, surviving neonates had a higher risk of permanent neurologic handicap. Our study indicates that the optimal management of the second stage of labour remains controversial.