Lifestyle Intervention of Diet and Exercise Limits Weight Gain and Complications in Obese GDM Women

Abstract

Evidence-based obstetrics indicate that exercise is an important component of a healthy pregnancy. In addition to exercise, weight gain restriction in obese women also may be beneficial in decreasing maternal and neonatal complications in pregnancy. PURPOSE: To determine the impact of diet and exercise on pregnancy outcomes and weight gain restriction in obese women with gestational diabetes mellitus (GDM) compared to diet alone. METHODS: 174 women diagnosed with GDM met inclusion criteria, 49 in the structured exercise group, 17 in the self-initiated exercise group, and 108 in the diet only group by choosing not to exercise or having contraindications to exercise. All women were provided an isocaloric meal plan and recorded blood glucose, daily food intake, and daily amount of physical activity achieved. The structured exercise program participants performed an exercise test to maximal effort and received an exercise prescription of 60% of maximal oxygen uptake. RESULTS: The exercise and diet only groups had similar maternal Body Mass Index (BMI) (33.2± 6.9 vs. 35.4 ± 8.7 kg/m2) at study entry as well as gestational age at study entry (29.1 ± 5.2 vs. 28.2 ± 6.2 weeks). Of those participating in exercise, 62% in the structured exercise group recorded weekly exercise while only 18% of those in the self-initiated exercise group reported weekly exercise compared to the diet only group (p<0.001). Weight gain per week was significantly lower in the exercise groups (0.2 ± 0.9 lb. vs. 0.7 ± 1.0 lb., p<0.01). Women who gained weight compared to those who had no weight change or loss were 2.6 times as likely to have a c-section (95% CI: 1.1-6.1, p<0.05). Obese pregnant women with BMI >35 kg/m2 at study entry were 4.7 times as likely to have a c-section (95% CI: 1.5-15.3, p<0.01) than normal/overweight women (BMI 18.5-29.9 kg/m2). A trend towards macrosomia was observed in women who gained weight (Odds Ratio: 1.6, 95% CI: 0.4-5.7, p=0.49) and women with BMI >35 kg/m2 (Odds Ratio: 3.2, 95% CI: 0.3-31.3, p=0.37), although not statistically significant perhaps due to small sample size. CONCLUSIONS: Lifestyle intervention of exercise and diet in obese women with GDM may diminish the burden of obesity and possibly reduce maternal and neonatal complications. Since women are often more motivated to make healthy lifestyle changes in pregnancy, this is an opportune time for healthcare providers to impact future lifestyle behaviors.