Risk of Breast Cancer

Risk of Breast Cancer

Most women will never get breast cancer. A woman’s risk of breast cancer depends on her age and other risk factors. Most women who get breast cancer have no risk factors other than growing older. And many women who have risk factors other than age never get breast cancer.

The chart below shows how many women (out of 100) will get breast cancer over the next 10 years. The risk of developing breast cancer increases with age. By finding your current age, you will see the risk of someone in your age group.

Number of Women Who Get Breast Cancer Over 10 Years
Age Estimated risk
Estimated risk for women in the United States. This information comes from Surveillance, Epidemiology and End Results (SEER) Cancer Statistics Review, 1975-2005, National Cancer Institute.
30 to 39 Less than 1 in 100
40 to 49 About 1 in 100
50 to 59 About 2 in 100
60 to 69 About 3 in 100
70 to 79 About 4 in 100

Breast Cancer Risk Factors

  • Age – Getting older raises the risk of breast cancer.
  • Family history – Having a mother, sister, or daughter who had breast cancer raises the risk.
  • Breast biopsy history – Having an abnormal finding on a past breast biopsy raises the risk of breast cancer.
  • Menstrual history – Having your first period at an early age (before age 12) raises the risk. Going through menopause late (after age 55) raises the risk.
  • Reproductive history – Having your first child later in life raises the risk of breast cancer. Never having children also raises the risk.
  • Menopause hormone therapy – Taking hormones for menopause (estrogen alone or estrogen plus progestin) raises the risk.
  • Obesity – Being obese (very overweight) raises the risk of breast cancer.
  • Alcohol use – Having more than one or two drinks a day raises the risk.
  • Other risk factors – It is rare, but some women are born with a gene that puts them at high risk for breast cancer. Having radiation treatment at a young age also raises the risk.