Postpartum depression (PPD) is a common mood disorder that occurs after delivery with a prevalence of approximately 10%. Recent reports have related placental corticotropin-releasing hormone (pCRH) to postpartum depressive symptoms. The aim of this study was to determine whether pCRH, ACTH, and cortisol (measured 48 h after delivery) and glucocorticoid and mineralocorticoid receptor genotypes (NR3C1 and NR3C2) and their interaction are associated with PPD. A longitudinal 32-week prospective study of five hundred twenty-five Caucasian depression-free women that were recruited from obstetric units at two Spanish general hospitals immediately after delivery. Of the women included in the sample, forty-two (8%) developed PPD. A strong association between PPD and the interaction between the pCRH and NR3C2 rs2070951 genotype was observed. The mean level of pCRH in rs2070951GG carriers with PPD was 56% higher than the mean in the CG and CC genotype groups (P < 0.00005). Carriers of the rs2070951GG genotype with high levels of pCRH had a higher risk of developing PPD (OR = 1.020, 95% CI 1.007-1.034, P = 0.002). This association remained even after controlling for variables such as neuroticism, obstetric complications and the number of stressful life events during pregnancy. There is an important interaction between pCRH 48 h postpartum and the NR3C2 rs2070951GG genotype. This interaction moderately associates with the presence of PPD. These results may open a new line of research and, if confirmed in other settings, will help to identify better risk predictors and the treatment for PPD.
Keywords: ACTH; Glucocorticoid receptor gene; Mineralocorticoid receptor gene; Postpartum depression; pCRH.