Neuroendocrine and psychosocial mechanisms in post-partum psychosis

Abstract

(1) Results from a study investigating psychosocial and neuroendocrine influences on post-partum psychosis are presented. Subjects were 43 pregnant women with histories of affective disorder (bipolar or schizoaffective disorder, n = 26; major depressive disorder, n = 17), together with 45 pregnant women without any psychiatric history. (2) At 36 weeks antenatal assessments were carried out of the women's psychiatric histories, current psychiatric state and also the occurrence of life events in the preceding year. They were then monitored for 6 months after delivery during which time psychiatric state and any further life events were recorded. Illness was defined according to Research Diagnostic Criteria (RDC); 22 high risk women and 3 control women were categorised as RDC ‘cases’ during the post-partum follow-up period. Fifteen of the bipolar/schizoaffective women (8 of whom subsequently became ill within 3 months of delivery) and 15 controls (all of whom remained well) also participated in a neuroendocrine test at 4 days post-partum when their growth hormone response to a challenge dose of the dopamine agonist, apomorphine, was measured. (3) The results showed that women with histories of depression and control women who became ill after delivery were three times more likely to have had a life event in the year preceding onset of illness than women from these subgroups who remained well. In contrast, for women with histories of bipolar or schizoaffective disorder, life events appeared to be unimportant. Instead bipolar/schizoaffective women who became ill showed an enhanced growth hormone response to the apomorphine challenge test compared to those who remained well and controls. (4) It is concluded that women with histories of bipolar or schizoaffective disorder who suffer a recurrence of illness after delivery may have a supersensitivity of the dopaminergic system, possibly related to an impairment in the down-regulation of the DA receptor system consequent upon oestrogen withdrawal that occurs with delivery of the placenta.