This is a review of obstetrical and gynaecological patients presenting to our maternity unit after clinic hours from 1991 to 1993. Patient data was collected prospectively. The number of patients seen after clinic hours increased by 35%, from 2241 in 1991, to 3014 in 1993. Analysis of data from 1991 revealed that the majority of patients were self referred, General Practitioner referrals accounting for only 9% of patients seen. Antenatal patients were the largest group at 77%, 10% were postnatal and 13% had gynaecological complaints. Unbooked patients presenting with first trimester bleeding accounted for one third of all antenatal patients. Thirty eight percent of patients seen were admitted. The number of out-of-clinic hours patients constituted a sizeable proportion of our hospital population. We conclude that this service is a necessary and important part of patient care at a large maternity unit.