Connection found between hormone therapy use and breast cancer

July 1, 2025

National Institutes of Health (NIH) researchers recently published results showing a connection between hormone therapy use and breast cancer risk in women under 55.

According to a release, the scientists “discovered that women treated with unopposed estrogen hormone therapy (E-HT) were less likely to develop the disease than those who did not use hormone therapy.” The opposite was found for women who used estrogen plus progestin hormone therapy (EP-HT). Their risk of breast cancer was higher than those who were not treated with hormone therapy. The longer women used EP-HT, the higher their risk was. Additionally, “the association between EP-HT and breast cancer was particularly elevated among women who had not undergone hysterectomy or oophorectomy.”

The scientists hope their findings will aid clinical decision making.

About the Author

Erin Brady

Managing Editor

Erin Brady is Managing Editor of Medical Laboratory Observer.

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