Do Induction Agent Requirements Predict Risk for Cesarean Delivery in Obese NTSV Women? [25L

Abstract

INTRODUCTION: Rates of obesity are rising in the United States. Given the morbidity associated with operative delivery in obese women, understanding predictors of cesarean delivery in this population is important. We aimed to determine whether utilizing misoprostol or balloon catheter for cervical ripening predicts delivery outcomes in obese women undergoing labor induction. METHODS: Electronic medical records were queried retrospectively for labor and delivery information for all nulliparous, term, singleton, vertex (NTSV) deliveries at Massachusetts General Hospital in 2014. We used logistic regression to assess the likelihood of cesarean delivery among non-obese (BMI less than 30) and obese women using labor induction methods as primary predictors. RESULTS: In the cohort of 1,536 NTSV women, 472 (31%) were induced and 224 (15%) were obese. Obese women were more likely to be induced (51% vs 27%, P<.0001) and undergo cesarean delivery after induction (42% vs 29%, P=.01) than non-obese women. Obese women who received both misoprostol and a balloon catheter were significantly more likely to undergo cesarean delivery than those who received misoprostol or oxytocin alone for cervical ripening (OR 2.78, 95% CI 1.13–6.88). Similar patterns emerged among women with an unfavorable cervix requiring at least misoprostol or a balloon catheter for ripening. The induction agents did not confer differential risks of cesarean among non-obese women. CONCLUSION: The finding that obese, nulliparous women who require two cervical ripening agents during induction have a 3-fold higher risk of cesarean delivery highlights the need for further research regarding optimal intrapartum management of obese women.