Combination oral contraceptive pills are among the most researched pharmaceutical agents. More than 90 million women use them worldwide. These agents provide safe and effective contraception. In recent years, controversy has arisen over oral contraception and cardiovascular side effects.
The International Federation of Fertility Societies developed a consensus statement concerning the risks and benefits of combined oral contraception. The incidence of venous thromboembolic events in women 15 to 44 years of age is less than 10 cases per 100,000 women per year. The incidence in women who use combined oral contraception and have a family history of venous thromboembolism increases to 30 cases per 100,000 women per year. Women not using contraceptives who are pregnant or in the immediate postpartum period have an incidence of 60 to 80 cases per 100,000 women per year. The main risk factors for venous thromboembolic events include advancing age, obesity and family history. The Federation concluded that the best method of reducing the incidence of venous thromboembolic events in women receiving oral contraception is to determine which women are at high risk for these events and to recommend alternative contraceptive methods in this group.
Other potential side effects of combined oral contraception include cerebral vascular accidents and acute myocardial infarction. These events are rare in this age group. Risk factors for these adverse events include smoking and hypertension. In the cases of acute myocardial infarction, 80 percent of the women smoked. In women who smoke, the risks and benefits of combined oral contraception need to be discussed, and smoking cessation should be encouraged.
The Federation stated that adverse publicity about combined oral contraceptives in 1995 caused many women to discontinue use of these agents. Because most women stopped using oral contraceptives without substituting other contraceptive methods, there was a significant increase in the number of unwanted pregnancies. This occurred despite the fact that combined oral contraceptives are relatively safe.
The Federation concluded that combined oral contraceptives are a safe and effective contraceptive method. The overall benefits of these agents far outweigh any of the risks. This is true for short- and long-term benefits. The Federation states that before combined oral contraceptive use is initiated, patients should be assessed for potential risk factors. In patients at high risk for adverse events, other contraceptive methods should be considered.