It is uncertain whether MHT will increase your personal risk of breast cancer since breast cancer risk varies based on the type of MHT plus a woman’s family history and overall health.
To date, the evidence shows that in North America, the estrogen in MHT does not cause, nor increase the risk for breast cancer overall.
In menopausal women, short-term MHT using estrogen will not increase a woman’s risk of developing breast cancer. However, MHT may slightly increase the risk for breast cancer in late menopause after 4 or more years of continuous use.
Some women are at high risk for breast cancer. Please discuss your personal risks when discussing MHT with your healthcare provider.
Risk Factors for Breast Cancer:
- Age (your risk increases significantly after age 55)
- Family history / genetics (e.g. BRCA 1 or 2; PALB 2 variants)
- Previous breast biopsy that showed abnormal cells
- Increased breast density on mammography
- Not bearing children (or having first child after age 30).
- Lack of exercise
- Excessive alcohol intake
- Obesity and weight gain after menopause
- Lack of breast-feeding after childbirth
Short-term use of MHT for symptom control and quality of life will have little effect on personal breast cancer risk. Longer use of MHT does increase breast cancer risk. Currently, the only proven strategy to reduce breast cancer deaths is early detection through mammography in women over 50.