OBJECTIVE The aim of this paper is to provide an overview of the work of a consultation-liaison (C-L) psychiatry service to an obstetric inpatient unit in a university affiliated teaching hospital, with the aid of a comprehensive clinical database. METHODS The MICRO-CARES clinical database system was used for prospective recording of data on all obstetric inpatients referred to the C-L psychiatry service and the hospital clinical database was used to compare referred inpatients with all obstetric inpatients. RESULTS Ninety patients were referred in 3 years, a referral rate of 1.2% of obstetric admissions. There was no bias in referral on age, but there were significantly more unmarried patients in the referred group (p < 0.001). Referred patients had a significantly prolonged length of stay: a mean of 9 days for referred patients, with 6 days for all obstetric patients (p < 0.001). The most frequent reasons for referral were: coping problems, depression, anxiety/fear and past history of major psychiatric illness. The most common DMS-III-R psychiatric diagnoses were: Personality Disorders (19%), Mood Disorders (17%), Schizophrenic Disorders (15%) and Adjustment Disorders (13%). At least one confirmed diagnosis was made in 77% of patients, but 42% of diagnoses remained differential. There were significantly more patients with diseases of the nervous system, endocrine and circulatory disorders in the referred group (p < 0.001). Recommendations of psychosocial interventions predominated over psychopharmacological interventions, and concordance with these was 97% and 98%, respectively. Issues in the relationship of obstetrics and psychiatric C-L services are discussed and future directions indicated. CONCLUSIONS The referral rate was low compared with other specialty units. This is probably due to factors inherent in obstetric practice. A wide spectrum of psychiatric disorders was referred, including a higher than expected number of women with postpartum psychotic disorders, the majority of whom were managed successfully in the obstetric ward. There is a need for increased liaison with obstetric and community services and for collaborative research, with a particular emphasis on the prevention of psychiatric morbidity associated with pregnancy.