Cesarean delivery among women with prolonged labor induction

The objective of this study was to determine characteristics associated with cesarean delivery among women with labor induction lasting over 24 h.

Women with live singleton pregnancies without prior cesarean delivery undergoing a labor induction lasting >24 h between September 2006 and March 2009 at Duke University Hospital were identified. Collected variables were compared between subjects by mode of delivery. A multivariate logistic regression model for the outcome cesarean delivery was constructed separately for nulliparous and parous women.

There were 303 women who met inclusion criteria. The overall cesarean delivery rate was 57% (n=172) and remained constant with time (P=0.15, test-for-trend). Nulliparous women having a cesarean delivery were more likely to be obese [adjusted OR (aOR) 2.00; 95% CI 1.05, 3.80] and have a larger fetus [aOR 1.11 (aOR for every 100 g increase in birthweight), 95% CI 1.03, 1.20] compared to those having a vaginal delivery.

Increasing BMI and birthweight were independent predictors of cesarean delivery among nulliparous women with prolonged labor induction. Despite this, after 24 h of labor induction, the overall mean cesarean delivery rate remained constant at 57%, and did not change with time. Among women having a vaginal delivery following a prolonged labor induction, we saw high rates of shoulder dystocia, operative vaginal delivery and severe perineal laceration.