Association Between Oral Contraceptives and Myocardial Infarction

Analysis of the association between oral contraceptive use and the development of myocardial infarction in women less than 50 years of age shows that cigarette smoking is the most important factor in increasing the likelihood of myocardial infarction. This effect is independent of oral contraceptive use but oral contraceptive use also appears to be a risk factor; however, their use in the absence of other predisposing factors appears to have only a small effect on increasing the risk of dying from myocardial infarction. This small increase is of the same order of magnitude as the increased risk of death from thromboembolic disease. Oral contraceptive users more than 30 years of age who have other factors that increase the likelihood of myocardial infarction appear to have a substantially higher death rate.