Prospective study of postpartum depression in an Israeli cohort: prevalence, incidence and demographic risk factors

Ninety four women and their first born children took part in a longitudinal study of maternal mental health during pregnancy and after delivery. The children's cognitive functioning was assessed at age 4 using the McCarthy scales, without knowledge of the mothers' psychiatric history or current health. As expected girls performed slightly better than boys and children from middle class and professional families did better than children from working class homes, as did children whose mothers had achieved at least one A level at school. Significant intellectual deficits were found in the children whose mothers had suffered with depression, but only when this depression occurred in the first year of the child's life. Marital conflict and a history of paternal psychiatric problems were independently linked with lower cognitive test scores; together with a working class home background these were the only factors that contributed to the deleterious effect of maternal postnatal depression.

Examined the prevalence of depression in a heterogeneous sample of 360 pregnant women. Subjects were assessed with respect to both depressive symptomatology and diagnostic status during pregnancy and after delivery. At both assessments, approximately 25% of the sample reported elevated levels of depressive symptomatology. In contrast, 10% of the women met diagnostic criteria for depression during pregnancy, and 6.8% were depressed postpartum. However, only half of the cases of postpartum depression were new onset (3.4%); the remaining women receiving a diagnosis in the postpartum had also been depressed during pregnancy. Finally, depression during pregnancy was related to different sociodemographic variables than was postpartum depression, suggesting that depression at these two times may be associated with different psychological or etiological factors.

In a two-stage screening procedure using the Edinburgh Postnatal Depression Scale and Goldberg's Standardised Psychiatric Interview, 232 women six months after delivery were compared with control women individually matched for age, marital status and number of children, obtained from general practitioner lists, who were not pregnant nor had had a baby in the previous 12 months. No significant difference in the point prevalence of depression at six months was found between the postnatal (9.1%) and control women (8.2%) nor in the six-month period prevalence (13.8% postnatal, 13.4% controls), but a threefold higher rate of onset of depression was found within five weeks of childbirth. The possible explanations relate to the long duration of depression in women with young children, and the stressful effect of childbirth and its psychosocial sequelae.