The present study aimed to seek for (1) a possible relationship between plasma AVP levels and the Edinburgh Postnatal Depression Scale (EPDS) score at 6–8 weeks postpartum, and (2) a possible relationship between PPD and factors like parity, BMI, maternal gender preference, type of delivery, gender of the baby, maternal age, history of abortion, women’s education level, husband’s education level, and breastfeeding status at 6–8 weeks postpartum. Here, AVP is linked to major depressive disorder.