Time series analysis of anxiety and depression during pregnancy to postpartum depression based on cross-lagged model

BACKGROUND Women are susceptible to anxiety and depression during pregnancy, but the temporal patterns of these emotions across gestation remain unclear. It is also uncertain whether anxiety and depression during pregnancy exert time-lagged effects on postpartum depression. AIM To explore the dynamic trends of anxiety and depression at different stages of pregnancy and their time-lagged effects on postpartum depression, providing a reference for emotional management during and after pregnancy. METHODS Data were collected from 572 women who underwent prenatal care and delivered at the Obstetrics Department of Suzhou Ninth People’s Hospital between January 2024 and June 2025. The χ 2 test was used to assess psychologically changes from early to late pregnancy. Pearson partial correlation and cross-lagged modeling were used to examine temporal relationships between prenatal anxiety/depression and postpartum depression. RESULTS Anxiety detection rates were 6.99% (40/572) in early pregnancy, 24.13% (138/572) in midpregnancy, and 16.96% (97/572) in late pregnancy, showing a significant fluctuation trend (χ 2 = 21.092, P < 0.001). Depression rates were 5.42% (31/572), 21.68% (124/572), 13.81% (79/572) and 16.08% (92/572) in early, mid, late pregnancy, and six weeks postpartum, respectively, also showing significant fluctuation trend (χ 2 = 13.619, P < 0.001). Pearson correlation revealed shows that anxiety and depression during early, middle, and late pregnancy were positively correlated (P < 0.001). From pregnancy to six weeks postpartum, anxiety and depression during pregnancy (early, middle, and late) correlated negatively with depression at six weeks postpartum (P < 0.001). Cross-lag modeling indicated that anxiety and depressive symptoms during pregnancy exerted significant time-lagged predictive effects on postpartum depression (P < 0.001). CONCLUSION Anxiety and depression during pregnancy demonstrate dynamic evolution and both have time-lagged predictive effects on postpartum depression.