Myocardial infarction and oral contraceptives

Myocardial infarction in younger women. Associated clinical features and relationship to use of oral contraceptive drugs

In a study of thromboembolism and oral contraceptive drugs, 136 cases of myocardial infarction in women aged 30 to 44 years were identified, a rare disease in women of this age group. Data from their hospital medical records were compared with those of several other groups, including women without chronic disease admitted for various acute or elective conditions unrelated to thromboembolism, patients with thromboembolic disease other than myocardial infarction, and women queried or examined in the National Health Survey. The following attributes were found to be associated with myocardial infarction in younger women: presence of diabetes; hypertension; history of increased cigarette smoking; and hypercholesterolemia. A history of the use of oral contraceptive drugs was found with greater frequency in cases than in controls. The literature on the possible association of myocardial infarction and the use of oral contraceptives was reviewed.

Acute coronary artery disease and oral contraceptives

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.