Web-Based Behavioral Intervention Increases Maternal Exercise but Does Not Prevent Excessive Gestational Weight Gain in Previously Sedentary Women

Innovative methods are warranted to optimize prenatal outcomes. This study's objective was to determine if a web-based behavioral intervention (BI) can prevent excessive gestational weight gain (GWG) by increasing physical activity (PA).Participants were randomized to usual care (UC; n = 21) or BI (n = 24) between 10 to 14 weeks gestation. GWG, PA, and diet were assessed at baseline, mid-, and late pregnancy.No differences in GWG or adherence to GWG recommendations presented between groups. Total UC MET-minutes significantly decreased from baseline to late-pregnancy (1,234 ± 372 MET-minutes, P = .013). Mid-pregnancy sustained PA was greater for BI than UC (20-minute PA bouts: 122 ± 106 vs. 46 ± 48 minutes/week, P = .005; 30-minute PA bouts: 74 ± 70 vs. 14 ± 24 minutes/week, P < .001), and greater for BI at mid-pregnancy compared with baseline (20-minute PA bouts: 61.3 ± 21.9; 30-minute PA bouts: 39.6 ± 14.8, both P < .05). BI energy intake at mid-pregnancy significantly increased from baseline (336 ± 127 kcals, P = .04) and was significantly greater than UC (2,503 ± 703 vs. 1,894 ± 594, P = .005).Sedentary pregnant women should increase PA but may need additional dietary counseling to prevent excessive GWG.