There is still a lot that we don’t know about what contributes to the development of breast cancer, but the factors below have been associated in many studies with an increased risk.
It is important to note that having a risk factor, or even a few of them, does not mean a woman will develop cancer. Most women, in fact, do not.
Conversely, many women who are diagnosed with breast cancer have no risk factors.
Those with questions or concerns about these risk factors should talk with their doctor.
• Advancing age
• Age at first period (risk is reduced the later menses starts)
• Age at menopause (risk is increased the later it is)
• Age at the time of first birth (the younger, the lower the risk)
• Family history of breast cancer (especially in first-degree relatives: mother, sister or daughter)
• Number of past breast biopsies (even if the findings are benign)
• Having a genetic marker (BRCA1, BRCA2)
• Having a personal history of breast cancer
• Race or ethnicity (white women are at a higher risk overall, but African-American women have higher death rates. African-American women younger than 45 have high rates of breast cancer.)
• Having dense breast tissue
• Having been treated with chest radiation
• Having taken the drug diethylstilbestrol (DES) or having a mother who was on DES during pregnancy