Moderate Risk Factors

Prior Breast Cancer Diagnosis

If you had breast cancer before, you have an increased risk of breast cancer returning. This risk may be three to four times higher than for women with no history of breast cancer.

Direct Family History

Your risk of breast cancer increase if your mother, sister or daughter ("first-degree" relative) has been diagnosed with the condition. If you have two first-degree relatives with breast cancer, your risk increases. The risk is greater if your relatives developed breast cancer before menopause or had cancer in both breasts. Having a male blood relative with breast cancer also increases a woman’s risk of the disease.

87 percent of women with breast cancer have no direct family history of the disease. This means all women should be aware of other risk factors and screening guidelines. A direct family history does not guarantee that you will get breast cancer.

High-Risk Breast Lesions

If you have a history of certain noncancerous (benign) conditions, there is an increased risk of breast cancer. These conditions include:

  • Changes in breast cells (breast atypia)
  • Lobular carcinoma in situ (LCIS)

Women with a history of these conditions are four to five times more likely to develop breast cancer. Women with either condition are offered more frequent breast cancer screening. This includes:

  • Breast exams twice each year
  • MRIs in addition to yearly mammograms

An oral medication to lower estrogen may be used to lower your cancer risk. These medicines are tamoxifen and raloxifene.


Maintaining a healthy body weight is important for lowering your risk of breast cancer. Carrying extra weight increases the risk for breast and other cancers. Extra weight means:

  • Overweight — body mass index higher than 25
  • Obese — body mass index higher than 30

This is particularly important for women after menopause.

Certain body types can also have a higher risk. For example, women who carry more fat in the waist area (apple-shaped). Losing weight is an important step to lowering your breast cancer risk.

Risk Factors for Breast Cancer

Strongest Risk Factors

Lesser Risk Factors

Other Risk Factors