Oral contraceptive use and risk of breast cancer.

The clinical impact of the association between oral contraceptive (OC) use and breast cancer risk is important given that OCs are the most commonly prescribed contraceptive agent and that more than a quarter of a million women are diagnosed as having breast cancer in the United States annually. Substantial changes to OC formulations have been made during the past decade, and this review focuses on recent OC trends and risks and benefits. We also have a better understanding of how estrogen affects breast carcinogenesis; research on this topic is ongoing and has the goal of decreasing breast cancer incidence and mortality.