Hormone Replacement Therapy (HRT) and Breast Cancer 

Hormone replacement therapy (HRT) can be an effective treatment for menopausal symptoms, but it has been a controversial topic as some types of HRT may increase your risk of breast cancer. 

What is HRT? 

Hormone Replacement Therapy (HRT) – also called Menopause Hormone Therapy (MHT), oestrogen replacement therapy, or post-menopausal hormone therapy – is a pharmaceutical treatment used for menopausal symptoms.  

Menopause is the moment when a woman stops menstruating, which is often accompanied by an array of symptoms, such as hot flushes, insomnia, headaches, mood disturbances and reduced sex drive. 

If you want to find out more about menopause, head over to our Menopause and Breast Cancer key factsheet. 

How does HRT work? 

When you are approaching or have experienced menopause, your sex hormones – oestrogen and progesterone – drop, which causes the menopause-related symptoms mentioned above. HRT works by replacing either both oestrogen and progesterone or simply oestrogen to help relieve these symptoms. 

The different types of HRT. 

There are two main types of HRT: combined HRT and oestrogen-only HRT.  

The most common type of HRT is combined HRT, which has both oestrogen and progesterone. Oestrogen-only HRT is only recommended if you have had your womb removed, a.k.a. hysterectomy, as taking oestrogen alone can increase your risk of uterine (womb) cancer. 

There are different ways to take HRT, such as in the form of tablets, skin patches, spray, gel, implant, intrauterine system, vaginal cream, gel, pessary or ring. 

Does HRT increase the risk of breast cancer? 

Some types of HRT can increase the risk of breast cancer. This might be due to increased oestrogen, which can cause some cancers to grow. However, the increased risk is small and will depend on the type of HRT and how long you take it for.  

There is a higher risk of breast cancer with combined HRT compared to oestrogen-only HRT which has little to no increased risk of breast cancer.  

The longer you use HRT, the greater your risk of breast cancer, particularly after five years of use. But, your risk decreases over time after you stop taking the treatment. The longer you take HRT, the longer it takes for your risk to go back down. If you take HRT for over 10 years, some increased risk may remain. 

Should you take HRT for your menopause symptoms? 

HRT may be a solution for managing difficult or severe menopausal symptoms. We recommend you consult a qualified healthcare professional (GP, nurse or gynaecologist) to discuss your symptoms, risks, benefits, treatment suitability and duration, before deciding. 

Read our key facts sheets to learn more about Hormone Replacement Therapy (HRT) and Breast Cancer. Dive deeper into HRT and Breast Cancer by reading our science review.