In a new study from Boston University’s Black Women’s Health Study, scientists found that African-American women who use oral contraceptives increase their risk of getting breast cancer. Researchers studied 54,000 participants for 12 years, 789 of whom developed breast cancer. Women who had taken the pill within the past five years and whose use lasted for 10 or more years had a 65 percent greater incidence of estrogen receptor negative cancer than among non-users. Estrogen receptor positive tumors are known to have a better prognosis than estrogen receptor negative breast cancer. The study, published online in Cancer Epidemiology Biomarkers and Prevention, was conducted by the Slone Epidemiology Center at Boston University School of Medicine. Lead investigator Dr. Lynn Rosenberg said that because oral contraceptive formulations have changed over time, it was necessary to study how recent formulations affect breast cancer risk.