Prenatal stressful life events increase the prevalence of postpartum depression: Evidence from prospective cohort studies.

Postpartum depression (PPD) occurs frequently among postpartum women. Stressful life events (SLE) have gradually been recognized as risk factors for PPD. However, research on this topic has produced equivocal results. The purpose of this study was to explore whether women who experienced prenatal SLE had a higher prevalence of PPD. Electronic databases were systematically searched until October 2021. Only prospective cohort studies were included. Pooled prevalence ratios (PRs) and 95% confidence intervals (CIs) were calculated using random effects models. This meta-analysis included 17 studies involving 9822 individuals. Women who experienced prenatal SLE had a higher prevalence for PPD (PR = 1.82, 95%CI = 1.52-2.17). In subgroup analyses, a 112% and 78% higher prevalence of depressive disorders (PR = 2.12, 95%CI = 1.34-3.38) and depressive symptoms (PR = 1.78, 95%CI = 1.47-2.17) were detected in women who experienced prenatal SLE. The effect of SLE on PPD at postpartum different time points differed: PR = 3.25 (95%CI = 2.01-5.25) for ≤6 weeks, PR = 2.01 (95%CI = 1.53-2.65) for 7-12 weeks, PR = 1.17 (95%CI = 0.49-2.31) for >12 weeks. No obvious publication bias was detected. The findings support that prenatal SLE increase the prevalence of PPD. The effect of SLE on PPD tends to slightly decrease during the postpartum period. Furthermore, these findings highlight the importance of screening for PPD as early as possible, particularly among postpartum women who have experienced SLE.