Summary:The Waikato Hospital experience of women admitted or seen in the Cardiology Outpatient Clinic who were under the age of 40 and whose diagnosis was a recent acute coronary occlusive episode was reviewed. It was found that there were nine admissions in eight women in this category between December 1971 and November 1973, plus one further patient who was seen with a recent acute ischaemic episode as an outpatient. The histories of these patients were reviewed and their risk factors surveyed. Of the nine women in the study, seven were taking oral contraceptives.As opposed to previous studies, not all the women in this study showed risk factors other than oral contraceptive usage. Three patients in this group taking oral contraceptives and who were thought to have definite coronary ischaemic episodes had no other major risk factor though two of the three were obese. It is thought probable that oral contraceptives containing oestrogens should be considered as a coronary risk factor in young women.