Abstract
Gestational diabetes mellitus (GDM) is associated with adverse maternal and neonatal outcomes and an increasing global prevalence. Preventive interventions during pregnancy may help mitigate these risks. This systematic review and meta-analysis evaluated randomized controlled trials assessing lifestyle, exercise, and pharmacologic interventions for the prevention of GDM. Comprehensive searches were conducted in PubMed, Scopus, Web of Science, Cochrane CENTRAL, and Google Scholar up to May 2025. The primary outcome was GDM incidence, and secondary outcomes included fasting glucose, gestational weight gain, maternal and neonatal outcomes, adherence, and safety. Nine randomized controlled trials were identified, of which seven involving 4,046 women were included in the meta-analysis. Pooled analysis showed that antenatal interventions significantly reduced GDM incidence (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.41-0.75). Lifestyle programs (OR 0.56, 95% CI 0.39-0.80) and exercise-only interventions (OR 0.63, 95% CI 0.40-1.00) were most effective. Improvements in fasting glucose, gestational weight gain, cesarean delivery, and macrosomia were observed without increased adverse events. Structured lifestyle and exercise interventions are effective, safe, and scalable strategies for preventing GDM.