Outcomes among patients with Class III obesity an Analysis by BMI Group: Retrospective Cohort Study

Objectives: Evaluate the rate of induction of labor, cesarean delivery, perineal laceration, postpartum hemorrhage, and APGAR scores in patients with Class III obesity by BMI subgroups Design: Retrospective Cohort Study Setting: University Hospital Population: Patients presenting for delivery at our University hospital with Class III obesity at the time of admission Methods: A retrospective chart review was conducted of patients with a pre-delivery BMI ≥ 40 who delivered between May 2016 – December 2020 at a single institution. Patients were divided into the following BMI groups: 40-44.9, 45-49.99, 50-59.99, ≥60. Demographic and other clinical features were analyzed using ANOVA and Fisher tests across BMI groups. Rates of labor induction and cesarean delivery were further analyzed by logistic regression. Main Outcome Measures: Cesarean delivery was our primary outcome. Results: We identified 1010 patients with pre-pregnancy BMI ≥40 who delivered in the study period, of which 545 met the study criteria. The median BMI in this population was 43.9 (IQR: 41.8-48.5, range 40.0 – 92.9). Twenty-seven percent of these patients delivered via cesarean section versus 12% for patients who presented in spontaneous labor. There were higher rates of induction seen in patients with BMI 50.0-59.9, this effect was not seen in patients with BMI 60 or higher. Regarding other outcomes studied, there was no statistically significant difference among BMI groups in terms of the rate of cesarean delivery, perineal laceration, postpartum hemorrhage, and APGAR scores. Conclusions: Rates of induction of labor are higher in patients with higher BMI, but an associated increase in Caesarean section was not seen. Further study is needed to evaluate outcomes for patients with a BMI of 60 and greater and more clarity is needed around recommendations for timing of induction of labor in patients with Class III obesity who are primiparous versus multiparous.