Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.
Skip to main content

An international collaboration, using data from more than 100,000 women with breast cancer from 58 epidemiological studies worldwide, has found that using menopausal hormone therapy (MHT) is associated with an increased risk of breast cancer, and that some increased risk persists for more than a decade after use stops.

Menopausal hormone therapy increases breast cancer risk for years © Shutterstock

The findings, published in The Lancet, suggest that all types of MHT, except topical vaginal oestrogens, are associated with increased risks of breast cancer, and that the risks are greater for users of oestrogen-progestagen hormone therapy than for oestrogen-only hormone therapy. For oestrogen-progestagen therapy, the risks were greater if the progestagen was included daily rather than intermittently (e.g. for 10-14 days per month).

Read more (University of Oxford website)