Post-partum psychosis is characterized by a rapid development of bizarre delusions, affective symptoms, sleeplessness and disorganized behaviour that jeopardizes the safety of the new-born baby and the mother as well as the long-term mental health of the infant. The incidence of psychosis within the first 3 months after delivery is 14 times higher than during the two years before pregnancy and leads to hospital admission in about one woman per 1,000 deliveries. A study of 1,133,368 first-time mothers in Sweden over a 29-year period found 1,413 hospitalized cases of post-partum psychosis. Breathing problems in the child, severe birth asphyxia, pre-term birth, caesarean section, perinatal death (of the infant) and small birthweight were all associated with an increased risk of postpartum psychosis. However, after adjustment for previous hospitalization for psychiatric problems only pre-term birth and caesarean section remained significant risk factors increasing risk by a factor of 1.2 and 1.3 respectively. Previous hospitalization for psychiatric problems increased the risk of postpartum psychosis more than a hundredfold.
A. Nager ... [et al] - Obstetric complications and postpartum psychosis : a follow-up study of 1.1 million first-time mothers between 1975 and 2003 in Sweden Acta Psychiatrica Scandinavica January 2008, 117, 12-19