Published by the National Cancer Institute
Introduction
Oral contraceptives (OCs) first became available to American women in the early 1960s. The convenience, effectiveness, and reversibility of action of birth control pills (popularly known as “the pill”) have made them the most popular form of birth control in the United States. However, concerns have been raised about the role that the hormones in OCs might play in a number of cancers, and how hormone-based OCs contribute to their development. Sufficient time has elapsed since the introduction of OCs to allow investigators to study large numbers of women who took birth control pills for many years.
This fact sheet addresses only what is known about OC use and the risk of developing cancer. It does not deal with other serious side effects of OC use, such as the increased risk of cardiovascular disease for certain groups of women. Recently, alternative methods of delivering hormones for contraception have been developed, including a topical patch, vaginal ring, and intrauterine delivery system, but these products are too new to have been tested in clinical trials (research studies) for long-term safety and other effects (1). They also are not covered in this fact sheet.
