Effects of obesity on labor Induction
Results from a prospective cohort study presented at the 65th Annual Clinical and Scientific Meeting of the American College of Obstetricians and Gynecologists in San Diego, California, shed new light on the effect of obesity on labor. Researchers from the University of Maryland Medical Center in Baltimore, hypothesized that obesity prolonged induction of labor (IOL), but their findings suggested otherwise.
For the study, the authors enrolled 99 women with singleton pregnancies who were undergoing IOL. Obstetric management was per the provider’s discretion, with IOL via misoprostol, cervical balloon, or intravenous oxytocin. The interval from the start of IOL to latent labor was the primary outcome; the secondary outcome was duration to active labor and delivery. Labor was considered prolonged if greater than 24 hours to latent labor and greater than 36 hours to active labor. Patients were analyzed by body mass index (BMI) <30, 30 to 39.9, and >40. Outcome of the 23 cesarean deliveries were excluded.
Among the 76 women whose deliveries were assessed, median BMI was 36; 17 had BMI <30; 37 had BMI 30 to 39.9; and 22 had BMI >40. Neither parity nor Bishop’s scores were significantly different in any of the BMI groups. Median duration to latent labor, active labor, and to delivery also did not differ (10.6 vs 9.6 vs 12.7 hours; 14.1 vs 15.0 vs 19.2 hours; and 18.5 vs 17.8 vs 20.6 hours). Time to achieve active labor did trend longer with increasing BMI (P = 0.49).
The authors concluded that prospectively analyzed induced labor curves were not significantly different among normal weight, obese, and severely obese women and that, regardless of BMI, IOL is a viable management option.
1. Fitzgerald G. Obesity effect on induction of labor duration. Poster 25R. Presented Tuesday, May 9, 2017 at the 65th Annual Clinical and Scientific Meeting of the American College of Obstetricians and Gynecologists. Obstet Gynecol. 2017;129(5) suppl:189S