Two hundred consecutive women from five Southampton general practices who were between 8 and 14 weeks postpartum were visited at home. Each subject was given the 30-item General Health Questionnaire (GHQ-30) and a standardized psychiatric interview. Thirty-seven (18%) were identified as 'cases' by the psychiatric interview. Eighty-nine (44.5%) scored highly on the GHQ. Analysis of the results indicates that slight modification of the content and a raised cut-off point of the GHQ-30 make it a useful screening instrument for postpartum psychiatric disorder.