Third-generation OCs are pills containing an estrogen dose of less than 50 g and either of two newer progestins desogestrel or gestodene. Ischemic heart disease results from an impediment to circulation that deprives the heart of adequate blood supply. Myocardial infarction heart attack is the resulting death of heart muscle cells. Ischemic heart disease can develop gradually from atherosclerosis, in which deposits on the walls of coronary arteries restrict blood flow to the heart muscle, or it can result from a thrombus, or clot, that suddenly blocks a coronary artery. Using OCs may somewhat increase heart attack risk, but risk is largely limited to older women who smoke or have high blood pressure.
Recent studies suggest risk less than twice that of nonusers.
For example, a recent US case-control study found that OC use increased risk by about 1.7 times. Relative risk is a measure of how much a particular factor influences the risk of a specified outcome. For example, a relative risk of 2 associated with a factor means that people with the factor face twice the risk of having a specified outcome that people without the factor have. There is no increase in the risk of myocardial infarction with increasing duration of use of combined oral contraceptives. There is no increase in the relative risk of myocardial infarction in past users of oral contraceptives.