Incidence of and social-demographic and obstetric factors associated with postpartum depression: differences among ethnic Han and Kazak women of Northwestern China

Background Studies on postpartum depression (PPD) in China have focused primarily on women of Han ethnicity, whereas work on other ethnic groups has proven limited. This study explored the ethnic differences of associated social-demographic and obstetric factors for PPD between Han-majority and Kazak-minority women in northwestern China. Methods Han and Kazak women who received routine examinations at four hospitals in a multi-ethnic area of China six weeks after childbirth between March 2016 and December 2016 were included in the study. Data on the women's socio-demographic characteristics, obstetric factors, and possible depression at six weeks after childbirth were collected. We examined the associated factors of PPD using multivariable logistic regression analyses by ethnic group. Results The overall incidence of PPD was 14.6% (184/1,263) at six weeks after childbirth. PPD was detected more frequently among Kazak (16.1%) than Han women (13.1%). Kazak women exhibited a higher risk of PPD (adjusted OR = 1.561, 95% CI [1.108-2.198], P = 0.011). Urinary incontinence (UI) represented a significant risk factor of PPD for Kazak compared with Han women (OR = 1.720, 95% CI [1.056-2.804], P = 0.003). In contrast, the presence of the mother-in-law as a caregiver after childbirth demonstrated a positive association with PPD among Han (OR = 2.600, 95% CI [1.499-4.512], P = 0.001), but not with Kazak women. Conclusions Kazak women were more likely to develop PPD than Han women, even after controlling for confounders. Moreover, distinct risk factors for PPD existed for Han and Kazak women. Future research that explores the relationships between Han women and their mothers-in-law as well as Kazak women's attitudes toward UI could help us further understand PPD in these populations.