A simple, accurate, and practical device was designed for detecting the woman at risk for postpartum emotional disorder (PED). Women attending the Sainte-Justine prenatal clinic were requested to complete a 19-item "yes/no" type of questionnaire. Each patient was classified for presence or absence of PED according to preestablished criteria. The responses of the patients classified as having emotional disorders were compared to the "normal" group. Thirteen percent developed PED. Six items showed predictive value: 1) admission of often feeling unloved by husband; 2) admission of feeling that pregnancy is undesired; 3) past history of postpartum depression; 4) being single or separated; 5) admission of marital problems; 6) admission that pregnancy was unplanned. The presentation of these items as part of a routine patient prenatal history questionnaire would constitute a means of identifying the woman at risk to develop PED and preventive measures could be taken.