Risk Factors for Breast Cancer

Being a woman and aging are the most significant risk factors for breast cancer — and, for more than 70 percent of women who develop the disease, the only identifiable ones. The risk of breast cancer increases as women get older, particularly after the age of 50; the majority of breast cancers are found in women 55 and older.

Beyond age and gender, there are other factors known to be associated, to varying degrees, with an increased risk of breast cancer. These are listed below in two major categories: those that cause moderately higher risk and those that cause risk to go up slightly. Even within these categories, not all of the risk factors carry the same level of risk, and having one or more doesn’t guarantee that the disease will occur. For more on understanding breast cancer risk, click on the following factors: