A follow-up study of postpartum psychoses: prognosis and risk factors for readmission.

OBJECTIVE: The aim of this study was to describe the prognosis and risk factors for the first readmission after postpartum psychosis. METHOD: Linking the Danish Medical Birth Register and the Danish Psychiatric Central Register from 1 January 1973 to 31 December 1993 revealed 1173 women diagnosed with a psychosis within 91 days of delivery. The relative risk (RR) of readmission was estimated using Cox proportional hazard regression models. RESULTS: An increased risk of readmission was found for women with a diagnosis of schizophrenia (RR = 2.4, 95% CI = 1.9-3.1) and for women with a history of previous psychiatric admission (RR = 1.8, 95% CI = 1.5-2.1) compared to first-admitted women with other functional psychoses. Unmarried women also showed an increased risk of readmission, and only preterm delivery was associated with a reduced risk of readmission. CONCLUSION: Preterm delivery predicts the best prognosis after postpartum psychosis. The majority of readmissions were related to the psychopathology of the patient and to lack of social support.