Objective <p>Although exercise is widely advocated for enhancing perinatal mental health, the optimal modalities for specific perinatal stages remain unclear. This study aimed to evaluate the comparative efficacy of various exercise types on perinatal depression, anxiety, and quality of life, and to formulate stage-specific recommendations for the antenatal and postnatal periods.</p> Methods <p>We conducted a systematic search of seven electronic databases (including PubMed and Embase) for randomized controlled trials (RCTs) investigating the effects of exercise interventions on perinatal mental health. The search spanned from inception to January 16, 2026. The methodological quality of the included trials was assessed using the Cochrane Risk of Bias tool. Random-effects models were utilised for data synthesis, with subgroup analyses examining the effects of exercise type and control group design.</p> Results <p>Thirty-two RCTs involving 4,189 participants were included. Exercise interventions significantly reduced the risk of antenatal (<i>P</i> = 0.02) and postnatal (<i>P</i> = 0.036) depression. Furthermore, exercise demonstrated efficacy in treating antenatal (<i>P</i> = 0.003) and postnatal (<i>P</i> = 0.01) depression, and in preventing antenatal anxiety (<i>P</i> = 0.007). Subgroup analyses revealed a stage-specific efficacy pattern: structured mind-body exercises (e.g.Yoga) yielded superior outcomes during the antenatal period, whereas structured aerobic exercise was more effective for treating postnatal depression. Notably, active control groups (e.g., health education, social support) attenuated the observed intervention effects compared with ‘no treatment’ controls.</p> Conclusions <p>This study supports a ‘stage-specific’ exercise prescription strategy, emphasising mind-body exercises such as yoga during the antenatal period to prevent depression and manage anxiety, while prioritising structured aerobic exercise postnatally to treat depression. Based on the effective protocols analyzed, a regimen comprising approximately three moderate-intensity (e.g., 55–75% of maximum heart rate or Borg RPE 12–14) sessions per week, each lasting 30–60&#xa0;min, appears beneficial for optimal mental health. Future guidelines should tailor exercise modalities to the specific perinatal stage.</p> Trial registration <p>PROSPERO: CRD420261280922.</p>