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Updated: Oct 2, 2025

An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Could Perimenopausal Estrogen Prevent Breast Cancer? Exploring the Differential Effects of Estrogen-Only Versus
Isaac Manyonda1, Vikram Sinai Talaulikar2, Roxanna Pirhadi3
1Department of Obstetrics and Gynaecology, St George's University Hospitals NHS Foundation Trust/St George's, University of London, London, UK.
Abstract:
Breast cancer is the commonest cancer among women in the western world, accounting for up to 30% of all cancers in women. There is a long-standing controversy about the potential link to hormone replacement therapy (HRT), with large observational studies suggesting that HRT increases the risk, while the Women's Health Initiative (WHI), a prospective, randomized placebo-controlled trial, has reported several times over a period of 20 years that combined (estrogen and progestogen) HRT increases the risk, while estrogen-only HRT given to women who have had a prior hysterectomy, is associated with a significantly reduced risk of developing breast cancer. Evidence from the randomized trial shows a significant reduction in both incidence of and mortality from breast cancer in women who took estrogen replacement therapy; this message needs to be presented clearly and robustly so that it can help women with decision making when considering HRT for menopause.
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