To evaluate the effects of supervised exercise on gestational diabetes mellitus (GDM) and other pregnancy outcomes and examine dose–response relationships.
Systematic review with random-effects meta-analysis and meta-regression.
Four databases were searched up to November 2025.
Randomised controlled trials in pregnant women comparing supervised exercise with usual care were included if they reported GDM. GDM was prespecified as the primary outcome, while other outcomes were extracted where available, including gestational hypertension (GH), pre-eclampsia, excessive gestational weight gain (EGWG), macrosomia, caesarean delivery, preterm birth and low birth weight.
Nineteen studies (n=6213; 48.6% in intervention groups) were included, with moderate certainty of evidence. Supervised exercise reduced the risk of GDM (risk ratio (RR) 0.74, 95% CI 0.57 to 0.96; I2=47%), GH (RR 0.55, 95% CI 0.40 to 0.77; I2=1%), EGWG (RR 0.75, 95% CI 0.61 to 0.92; I2=70%) and macrosomia (RR 0.61, 95% CI 0.46 to 0.81; I2=27%). Subgroup analyses for these outcomes suggested greater effects with earlier intervention (initiated in early pregnancy or duration >20 weeks), higher adherence (≥80%), combined aerobic and resistance training, and weekly exercise duration ≥150 min/week. Significant subgroup differences in GDM risk were observed for intervention initiation timing (p=0.009) and intervention duration (p=0.010). Dose–response analysis showed a peak effect at approximately 500–550 metabolic equivalent task-minutes per week for EGWG, with a plateau at higher doses.
Supervised exercise during pregnancy reduces adverse pregnancy outcomes when initiated early, with high adherence, at moderate doses, and with combined aerobic and resistance training.