Altered functioning of the HPA axis in depressed postpartum women

•HPA axis functioning was evaluated at remote puerperium in depression.•Cortisol awakening response was higher in healthy controls than postpartum women.•Cortisol diurnal variation was lower in depressed women compared with other groups.•The remote puerperium presents an attenuation of the HPA axis reactivity.•HPA axis malfunctioning is more pronounced in the presence of depressive episodes.

BackgroundThe present study aimed to evaluate the relationship between the functioning of the hypothalamic-pituitary-adrenal (HPA) axis and major depressive episodes in the remote postpartum period.MethodsThe sample (mean age, 28.0±5.3 years) consisted of 37 depressed postpartum women (DPP), 42 euthymic postpartum women (EPP) and 25 non-postpartum healthy women (HC). Salivary cortisol samples were collected immediately after awakening and 30 min, 3 and 12 h later, at approximately the sixth month postpartum (mean, 169.6±60.3 days).ResultsDifferences in cortisol levels were observed at awakening (DPPEPP=HC). The relative increment in the cortisol awakening response (CARi%) was significantly higher in HC (113.5±94.3) than in EPP (63.1±69.8) and DPP (32.2±49.6). The relative reduction in diurnal variation (DVr%) was lower in DPP (56.5±41.8) than in EPP (75.6±22.4) and HC (75.1±13.0).LimitationsThe main limitation was cortisol collection on a single day and without measurement at midnight.ConclusionsOur findings suggest that the remote postpartum period involves attenuation of HPA axis reactivity; this dysregulation is more pronounced in the presence of DPP, which is associated with a reduction in cortisol diurnal variation. Abnormalities in the neuroendocrine system related to stress processing, present even several months after delivery, can represent vulnerability to mental disorders. Thus, improvements in the mental health care of postpartum women are needed.