Do Birth Control Pills Cause Breast Cancer?
After more than 50 studies, most experts believe that pills have little, if any, effect on the risk of developing breast cancer. The Women’s Care Study of 4575 women with breast cancer and 4682 controls found no increased risk for breast cancer (RR: 1.0) among women currently using pills and a decreased risk of breast cancer (RR: 0.9) for those women who had previously used pills. Use of pills by women with a family history of breast cancer was not associated with increased risks of breast cancer, nor was the initiation of pill use at a young age. [Marchbanks ? 2002] However, several studies have shown that current users of pills are slightly more likely to be diagnosed with breast cancer (Relative Risk: 1.2). [Collaborative Group; Lancet 1996] Two factors may explain the increased risk of breast cancer being diagnosed in women currently taking pills: 1) a detection bias (more breast exams and more mammography) or 2) promotion of an already present nidus of cancer cells. Ten years afte
