Research

Hormonal

The increased risk of breast cancer mortality is associated with five or more years of postmenopausal hormone therapy, with a relative risk of death of 1.45.

Long-term use of estrogen (5+ years) is linked to a higher risk of dying from breast cancer. This underscores the importance of regular screening and discussing the duration of therapy with your doctor.

StrongSupportsMEDIUM confidence
The relative risk of death due to breast cancer was 1.45 (95 percent confidence interval, 1.01 to 2.09) among women who had taken estrogen for five or more years.
Graham A. Colditz et al. · New England Journal of Medicine · 1995

Why this rating

Prospective cohort with high follow-up completeness for fatal cancer.

Source

The Use of Estrogens and Progestins and the Risk of Breast Cancer in Postmenopausal Women

Graham A. Colditz et al. · New England Journal of Medicine · 1995

DOI 10.1056/nejm199506153322401

cohort · n=69586Cited 1,509×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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