Gestational Weight Management in Underserved Mothers in the U.S

INTRODUCTION: Underserved pregnant individuals experience a high risk for weight gain outside clinical guidelines and adverse perinatal outcomes. The federal Special Supplemental Nutrition Program for Women, Infants, and Children assists underserved pregnant individuals with supplemental nutrition. Special Supplemental Nutrition Program for Women, Infants, and Children is positioned to disseminate interventions that promote recommended gestational weight gain, increase access to efficacious programs, and complement clinical care. METHODS: Pregnant Special Supplemental Nutrition Program for Women, Infants, and Children participants were randomly assigned (2019‐2023) to a codeveloped multicomponent electronic health intervention for gestational weight gain management or usual care between 10 and 16 weeks of gestation. The primary outcome (analyzed in 2025) was gestational weight gain guideline attainment. Secondary weight outcomes included study‐observed weight gain, weekly weight gain, deviation from guidelines, fat mass gain, and change in energy balance behaviors. Adverse perinatal outcomes were explored. RESULTS: Pregnant participants (n=351; 57% non‐Hispanic Black) were enrolled (179 intervention, 172 usual care) across 31 Special Supplemental Nutrition Program for Women, Infants, and Children clinics. The incidence of guideline attainment was not different between groups (both groups: 17%; OR=1.05; 95% CI=0.55, 2.01; p=0.89). Study‐observed weight gain (adjusted mean difference= ‐1.4 kg; 95% CI= ‐2.8, ‐0.1; p=0.04), rate of weight gain (adjusted mean difference= ‐0.07 kg/wk; 95% CI= ‐0.13, ‐0.01; p=0.02), deviation from guidelines (adjusted mean difference= ‐0.05 kg/wk; 95% CI= ‐0.10, ‐0.00; p=0.03), and fat mass gain (adjusted mean difference= ‐1.3 kg; 95% CI= ‐2.1, ‐0.6; p<0.001) were lower in the intervention group than in the usual care group. Change in energy intake was lower in the intervention group (306 kcals/day; 95% CI= ‐500, ‐112; p=0.002). There were 43 cases (9% intervention, 16% usual care) of preterm birth and 30 neonatal intensive care unit admissions (7% intervention, 11% usual care). CONCLUSIONS: A remotely delivered lifestyle intervention concomitant with Special Supplemental Nutrition Program for Women, Infants, and Children care reduced gestational weight gain and fat mass gain. This approach demonstrates the potential for scalable interventions integrated into existing public health systems to expand access and inform public health strategies targeting maternal health disparities. TRIAL REGISTRATION: This study is registered at www. CLINICALTRIALS: gov NCT04028843.