Investigated the relationship between plasma cortisol, prolactin, oestrogen, progesterone, thyroxine, thyrotropin (or thyroid) stimulating hormone (TSH), and early postpartum depressive symptoms in 23 pregnant (mean age 27.8 yrs), 70 postpartum women (mean age 30.8 yrs) at 7 days postpartum, and 38 non-gravid controls (mean age 36.2 yrs). 62 postpartum Ss were screened for depression by the Edinburgh Postnatal Depression Scale (EPDS) on day 7 after delivery and 34 postpartum Ss were assessed by the Present State Examination 2 weeks after delivery. Postpartum women had a significantly ± (PSE) at 8 greater level of cortisol, prolactin, thyroxine and oestrogen than non-puerperal 11) had significantly ≥ women. Postpartum women with current depression (EPDS lower plasma prolactin levels than those without depression, and those who 5) had ≥ developed depression within 6-10 wks after delivery (PSE level significantly lower plasma prolactin and significantly greater progesterone levels than those who were not depressed. Women who had previous episodes of depression had significantly greater EPDS and PSE scores, lower prolactin, and higher TSH levels than those who had not suffered from previous episodes of depression.