Reduced incidence of gestational diabetes with bariatric surgery.

Background: Obesity is a risk factor for gestational diabetes mellitus (GDM), and bariatric surgery is an effective treatment for obesity. Our objective was to determine the association of bariatric surgery with the incidence of GDM and related complications.

Study Design: We performed a retrospective study comparing rates of GDM and related outcomes (including cesarean section, large-for-gestational-age infant, shoulder dystocia, and infection) between a group of women with a delivery before bariatric surgery and a group with a delivery after bariatric surgery. We used a private insurance claims database with information on 23,594 women who had bariatric surgery between 2002 and 2006. The dataset was searched to identify women with codes for bariatric surgery and a pregnancy resulting in a delivery at greater than 22 weeks gestation. Incidences of GDM and selected delivery complications for delivery before versus after bariatric surgery were compared using Fisher exact test and logistic regression.

Results: There were 346 women who had a delivery before bariatric surgery, and 354 had a delivery after bariatric surgery. Women with delivery after bariatric surgery had lower incidences of GDM (8% vs 27%, odds ratio (OR) 0.23, (95% CI 0.15 to 0.36) and cesarean section (28% vs 43%, OR0.53, 95% CI 0.39 to 0.72) than those with delivery before bariatric surgery.

Conclusions: Bariatric surgery is associated with a decreased incidence of GDM and cesarean section in subsequent pregnancies. This potential effect of bariatric surgery should be considered in the management of obese women of childbearing age. Prospective studies are needed to confirm these findings.