Objective: Postpartum depression (PPD) represents a significant threat to maternal-child health. Although PPD is common, with an estimated prevalence of 10% to 15%, critical questions concerning its etiology remain unanswered. Existing studies seem to provide conflicting evidence regarding the relation between placental corticotrophin-releasing hormone (pCRH) and the development of PPD. The purpose of the present investigation was to determine whether maternal prepartum hypothalamic-pituitary-adrenal and placental dysregulation, in particular elevated midgestational pCRH, represent markers of risk for the development of PPD symptoms.
Methods: One hundred seventy adult women with singleton, term pregnancies were recruited during the first trimester and participated in study visits at 15, 19, 25, 31, and 36+ weeks' gestation and at 3 and 6 months postpartum. At each prenatal visit, blood samples were obtained and assayed to determine maternal cortisol, adrenocorticotropic hormone, and pCRH concentrations. Depressive symptoms were assessed at all visits.
Results: Depressive symptoms at 3 months postpartum were associated with elevated midgestational pCRH (partial r = 0.26; p < .01) and also accelerated trajectories of pCRH (B values ranged from 6.9 to 8.3, p < .05). Placental CRH was not predictive of PPD symptoms at 6 months postpartum. Furthermore, prepartum cortisol and corticotrophin profiles were not associated with PPD symptoms.
Conclusions: The current prospective study provides results that reconcile both the positive and negative findings in the existing literature and identifies elevated pCRH as a marker of risk for the development of PPD symptoms.