Other shared factors are older age, obesity, never carrying a pregnancy to term or never falling pregnant, and long-term use of hormone replacement therapy after menopause.

Some women try to lower their cancer risk through preventive (prophylactic) surgeries, such as a mastectomy (removal of the breasts) or an oophorectomy (removal of the ovaries and fallopian tubes).

For some high-risk individuals, doctors may prescribe medications like tamoxifen to help reduce the chances of developing breast cancer.