Research

Hormonal

Breast cancer risk increased with duration of unopposed estrogen use.

Longer durations of unopposed estrogen therapy may necessitate closer monitoring for breast cancer risk.

GoodSupportsmedium confidence
Breast cancer risk increased with duration of unopposed estrogen use among longer-term users.
Wendy Y. Chen et al. · Archives of Internal Medicine · 2006

Why this rating

Based on a prospective cohort study design.

Source

Unopposed Estrogen Therapy and the Risk of Invasive Breast Cancer

Wendy Y. Chen et al. · Archives of Internal Medicine · 2006

DOI 10.1001/archinte.166.9.1027

cohort · n=28835Cited 249×
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DOI resolved against Crossref · corpus check 2026-06-10

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