Women with gene mutations that increase their likelihood of developing
breast cancer have an even greater risk if they used oral contraceptives at
an early age or before 1975, according to new findings by researchers at the
University of Toronto, in Ontario (J Natl Cancer Inst. 2002;94:1773-1779).
Women with mutations in the BRCA1 and BRCA2 genes have a 50% to 80% lifetime risk of developing
breast cancer. To determine whether oral contraceptive use influences that
risk, the researchers performed a case-control study on 1311 pairs of women
who were carriers of deleterious mutations in one or both of these genes,
half of whom had breast cancer and half of whom did not.
Stephenson J. Breast Cancer Risk. JAMA. 2003;289(2):164. doi:10.1001/jama.289.2.164-a