Reducing postpartum weight retention is a promising strategy for addressing the rising prevalence of overweight and obesity in women. This systematic review and meta-analysis explored whether lifestyle interventions during pregnancy have the potential to reduce weight retention at 4 months postpartum and beyond. A search of five electronic databases for randomized controlled trials comparing the effect of weight-related lifestyle interventions beginning in pregnancy on postpartum weight retention to standard prenatal care groups was performed. Postpartum weight retention data was synthesized in a random-effects meta-analysis. Data from 14 studies of 7116 participants showed that the intervention group retained statistically significant less weight than the control group (weighted mean difference: -0.73 kg, 95% CI: -1.32 to -0.14, P = 0.015). Subgroup analysis showed this effect to be largest in studies with follow-ups from 4 to 6 months (weighted mean difference: -1.32 kg, 95% CI: -2.11 to -0.53, P = 0.001), but it remained significant until 12 months postpartum (weighted mean difference: -0.68 kg, 95% CI: -1.28 to -0.09, P = 0.023). In studies of women with a body mass index above 25.0 kg/m(2) , no significant intervention effect was observed. More high-quality studies with a follow-up beyond 12 months postpartum are needed.