Risks Associated with Cesarean Delivery during Prolonged Second Stage of Labor

ABSTRACT Background Data regarding maternal and fetal morbidities is limited with regard to surgical morbidity per each additional hour in the second stage. Objective To quantify perinatal morbidities associated with cesarean delivery by length of second stage. Methods This is a retrospective cohort study of cesarean deliveries during the second stage of labor using the Consortium on Safe Labor database. All term, singleton gestation in cephalic presentation were included. Women with stillbirth or contraindications to vaginal delivery were excluded. Groups were divided by length of second stage: ≤3 hours, 3-4 hours, 4-5 hours, 5-6 hours, and >6 hours. The primary outcome was a composite of maternal morbidities. Secondary outcomes were a composite of neonatal morbidities as well as individual maternal and neonatal morbidities. Baseline demographic and clinical characteristics were compared between groups. Univariate and multivariate analyses were performed. Results We included 6,273 women in total. 3,652 (58.2%) women had a second stage of ≤3 hours, 854 (13.6%) of 3-4 hours, 618 (9.9%) of 4-5 hours, 397 (6.3%) of 5-6 hours, and 752 (12.0%) of >6 hours. Neither the maternal nor neonatal morbidities composite outcomes were statistically different between groups. Extended maternal length of stay (>5 days), increased birthweight, and lower rates of general anesthesia were associated with an increased length of second stage. Chorioamnionitis, wound complications, postpartum hemorrhage, and thrombosis did not increase over time. Conclusion Women should be counseled about duration of the second stage of labor, which should include a discussion of the risks associated with a cesarean delivery with a prolonged second stage. However, these risks may not be as high as anticipated.