But tamoxifen can cause cancer of the lining of the uterus in post-menopausal women.

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This keeps the lining of the uterus healthy and ready to nourish a developing foetus.

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Every three months, the women were given another hormone to protect the lining of the uterus, and cause period-like bleeding.

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By suppressing ovulation, it actually reduces the risk of two types of cancer: ovarian, which affects the ovaries and endometrial, which affects the lining of the uterus.

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Irregular bleeding can also be the result of endometrial polyps, overgrowths in the lining of the uterus, and can even be a sign of pre-cancer or cancer of the uterus.

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Endometrial polyps are typically identified during the evaluation of abnormal bleeding and may be found either on ultrasound or by endometrial biopsy, an office procedure that samples the lining of the uterus.

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It turns out that cells can flake off of tumors in the ovaries or the lining of the uterus, and float down to rest in the cervix, where Pap tests are performed.

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