Postpartum depression (PPD), as a common complication of childbearing, could have adverse consequences on mothers, children, and families. This cohort study aimed to assess the association between duration of folic acid (FA) supplementation during pregnancy and the onset of PPD in Chinese women. A total of 1592 participants were recruited, and data collected between July 2015 and March 2017 in Tianjin, China. Participants' baseline data were collected regarding socio-demographic and lifestyle characteristics, obstetric history, and FA supplementation during pregnancy. The Chinese version of the self-rating depression scale was used to assess depressive symptoms at 6-12 weeks postpartum, and the prevalence of PPD in participants was 29.4%. Pregnant women who took FA supplements for >6 months had a lower prevalence of PPD, compared to those who took FA for ≤6 months. After using the 1:1 ratio propensity score matching, 601 FA-users ≤ 6 months and 601 FA-users > 6 months were included in the further analyses; this also yielded similar results (P < 0.05). Logistic regression analysis showed that FA intake for >6 months was an independent determinant of PPD (odds ratio = 0.76; 95% confidence interval: 0.59-0.98; P < 0.05). Thus, prolonged FA supplementation during pregnancy was associated with a decreased risk of PPD in Chinese women.
Keywords: folic acid; postpartum depression; propensity score matching; supplementation duration.