[Impact of placental hormone withdrawal on postpartum depression].

Prenatal and postpartum measurements of serum beta-hCG, estradiol (E2) and progesterone (P) concentration were done by radioimmunoassay in 20 cases of postpartum depression (PD) and 20 cases without postpartum depression (NPD). The results showed significantly higher serum levels of P and beta-hCG (at 36-37 gestational week) in PD, but no difference in the serum P and beta-hCG concentration between the PD and NPD after childbirth. The falling of the two hormones was faster in PD than in NPD. In neither prenatal nor postpartum test was any difference seen in serum E2 concentration between PD and NPD. These results suggest that supposely, the endogenous risk factor, the rapid withdrawal of the placental hormones (P and beta-hCG) after delivery, leads to PD.