Encouraging appropriate gestational weight gain in high-risk gravida: A randomized controlled trial

Excessive gestational weight gain (GWG) can increase pregnancy morbidity and is particularly problematic for women with pregestational obesity. A lifestyle modification intervention was introduced to gravida with obesity to decrease excessive GWG as compared to usual care (UC).

A randomized controlled trial was conducted to improve healthy lifestyle behaviors to manage appropriate GWG. Consenting participants with prepregnancy obesity and singletons ≤17 weeks were randomized to (1) Usual Care (UC): usual written educational materials and counseling by obstetric provider or (2) Enhanced Care (EC): UC plus (a) personalized letter from physician detailing appropriate GWG; (b) access to individualized GWG chart; (c) ongoing counseling with registered dietitian/nutritionist (RDN). The primary outcome was proportion with GWG ≤9.1 kg, as this is upper limit recommended by Institute of Medicine (IOM). Total GWG and GWG as less than/within/greater than IOM recommendations (in aggregate and stratified by obesity class), and pregnancy/neonatal outcomes were evaluated as secondary outcomes.

Analyses included 105 participants in EC and 109 in UC arms. The groups had similar demographics: 46% with class I obesity, 26% class II, and 28% class III. There were no group differences for any GWG, pregnancy, or neonatal outcomes when analyzed in aggregate. As compared to those randomized to the EC arm, participants in UC arm with class I obesity gained 1.4 kg less and those with class II obesity were significantly more likely to gain within IOM guidelines (14.8% vs. 40.0%, adjusted p = 0.04). Participants with class III obesity randomized to EC arm were more likely to gain within IOM guidelines as compared to participants randomized to UC arm (29.0% vs. 6.7%, adjusted p = 0.02).

There were no differences in GWG observed between groups when analyzing participants in aggregate. However, a physician's letter detailing appropriate GWG, patient portal access to a personalized GWG chart, and RDN consultation were helpful for encouraging GWG within IOM guidelines for women with prepregnancy class III obesity. Women with class I or II obesity had better GWG outcomes without these additional interventions.