Patient information leaflet from The Menopause Partnership (GP-led specialist care for women).
Understanding HRT and cancer risk
Many women are concerned about the relationship between Hormone Replacement Therapy (HRT) and cancer risk. It is important to understand that risk varies depending on the type of HRT used, how long it is taken, and an individual’s medical history.
For most healthy women under the age of 60, or within 10 years of menopause, the overall benefits of HRT outweigh the risks.
HRT and breast cancer
The relationship between HRT and breast cancer depends on the type of HRT:
Oestrogen-only HRT
In women who have had a hysterectomy and take oestrogen alone, research shows little or no increase in breast cancer risk. Some studies suggest the risk may be slightly reduced.
Combined HRT (oestrogen and progesterone)
Combined HRT is associated with a small increase in breast cancer risk, particularly with longer-term use beyond five years. The risk increases gradually with duration of use and reduces after stopping HRT.
It is important to note:
- The increase in risk is small for most women.
- The level of risk is similar to that associated with factors such as being overweight or drinking alcohol.
- The risk falls after stopping treatment.
Type of progestogen may influence risk. Micronised progesterone appears to be associated with a lower risk profile compared with some synthetic progestogens, although long-term data are still evolving.
HRT and other cancers
Endometrial (womb) cancer
Oestrogen-only HRT increases the risk of endometrial cancer if the uterus is present. For this reason, women with a uterus must take progesterone alongside oestrogen to protect the womb lining.
Ovarian cancer
There is a very small increase in ovarian cancer risk associated with HRT use. The overall risk remains low.
Bowel cancer
Combined HRT has been associated with a reduced risk of bowel (colorectal) cancer.
Factors that influence risk
Breast cancer risk is influenced by multiple factors, including:
- Age
- Family history
- Body weight
- Alcohol intake
- Pregnancy and breastfeeding history
- Lifestyle factors such as exercise and diet
HRT is one of many factors, and risk should always be considered in the context of an individual’s overall health profile.
Individualised decision-making
HRT is not usually recommended for women with a history of breast cancer unless advised by a specialist.
For women with a family history of breast cancer, HRT may still be appropriate, depending on individual risk assessment.
A personalised discussion should consider:
- Severity of menopausal symptoms
- Age and time since menopause
- Cardiovascular and bone health
- Individual cancer risk
Shared decision-making is central to safe and appropriate prescribing.
When to seek medical advice
You should seek medical advice if you notice new breast changes such as a lump, skin changes, nipple discharge, or persistent breast pain. Routine breast screening should continue as recommended for your age group.
If you have concerns about your cancer risk or family history, a clinical review can help guide appropriate screening and treatment decisions.
Summary
The relationship between HRT and cancer risk is complex and depends on the type of HRT used, duration of treatment and individual risk factors. For many women, particularly those under 60 or within 10 years of menopause, the benefits of HRT in improving quality of life and protecting bone and heart health outweigh the small associated risks.
An individualised assessment with a menopause specialist can help you make an informed and confident decision about treatment.
