ABSTRACT: To evaluate the prevalence and risk of antenatal and postpartum mental disorders among obese and overweight women.Seven databases (including MEDLINE and ClinicalTrials.gov) were searched from inception to January 7, 2013, in addition to citation tracking, hand searches, and expert recommendations.Studies were eligible if antenatal or postpartum mental disorders were assessed with diagnostic or screening tools among women who were obese or overweight at the start of pregnancy. Of the 4,687 screened articles, 62 met the inclusion criteria for the review. The selected studies included a total of 540,373 women.Unadjusted odds ratios were pooled using random-effects meta-analysis for antenatal depression (n=29), postpartum depression (n=16), and antenatal anxiety (n=10). Obese and overweight women had significantly higher odds of elevated depression symptoms than normal-weight women and higher median prevalence estimates. This was found both during pregnancy (obese odds ratio [OR] 1.43, 95% confidence interval [CI] 1.27-1.61, overweight OR 1.19, 95% CI 1.09-1.31, median prevalence: obese 33.0%, overweight 28.6%, normal-weight 22.6%) and postpartum (obese OR 1.30, 95% CI 1.20-1.42, overweight OR 1.09, 95% CI 1.05-1.13, median prevalence: obese 13.0%, overweight 11.8%, normal-weight 9.9%). Obese women also had higher odds of antenatal anxiety (OR 1.41, 95% CI 1.10-1.80). The few studies identified for postpartum anxiety (n=3), eating disorders (n=2), or serious mental illness (n=2) also suggested increased risk among obese women.Health care providers should be aware that women who are obese when they become pregnant are more likely to experience elevated antenatal and postpartum depression symptoms than normal-weight women, with intermediate risks for overweight women.