Results of oral contraceptive epidemiologic studies regarding neoplastic and cardiovascular effects.

Over the past three decades, much of the research on oral contraceptives has focused on cardiovascular and neoplastic effects. Results of recent United States studies have shown no increased risk of death among users of oral contraceptives, although an increased risk of idiopathic venous thromboembolism has been a consistent finding. There is compelling evidence that oral contraceptive use provides significant protection against endometrial and ovarian cancer, and that this protection lasts at least 15 years. In addition, no clear association has been found between oral contraceptive use and breast cancer or cervical cancer. Data on hepatocellular carcinoma and malignant melanoma are inconclusive.