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I stopped taking hormone replacement therapy after I read it could increase my risk of breast cancer. Will my risk return to normal now?

A recent study has shown that breast cancer risk begins to return to normal about six months after a woman stops taking a combination of the hormones estrogen and progestin. The study, part of the National Institute of Child Health and Human Development Women's Contraceptive and Reproductive Experiences Study, also confirmed that daily combined hormone therapy increases the risk of breast cancer.

The study involved more than 3,800 white and African-American women. About half the women had developed breast cancer and half did not. Both groups were questioned about their hormone use.

The researchers found that the women who took combined hormone therapy daily were one-and-a-half times more likely to develop breast cancer than the women who were not on the therapy. The risk increased with the length of time the women took the hormones. However, six months after the women stopped the therapy, their risk of breast cancer began to return to normal. This was true regardless of how long the women had been taking the hormone replacement.

The risks and benefits of combined hormone therapy were first studied by the National Institutes of Health's Women Health Initiative (WHI). Last July, WHI researchers stopped the study when it became clear that the risks of breast cancer and heart disease from combined hormone therapy outweighed the possible benefits.

Before these findings, combined hormone therapy was prescribed widely for menopause symptoms, such as hot flashes, night sweats, insomnia, and vaginal dryness.

Women considering hormone therapy should talk with their doctor about the possible risks and benefits before making a decision. For more information about hormone use and cancer, call the Cancer Information Service at 1-800-4-CANCER.


Source: "Ask the CIS" by the Cancer Information Service. "Ask the CIS" is distributed by the Cancer Information Service (CIS) of the Heartland, which serves Kansas, Nebraska, Missouri & Illinois. The CIS is a program of the National Cancer Institute. Call the CIS toll-free at 1-800-4-CANCER (1-800-422-6237) between 9 a.m. and 4:30 p.m. local time.

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Last update: Tuesday, November 25, 2008




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