For example, obesity actually appears to be protective for premenopausal breast cancer, whereas it is a risk factor for postmenopausal breast cancer.

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But in the premenopausal years, a woman's sex hormones start to change.

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Weight gain of 25 to 35 pounds is normal in pregnancy and not associated with an increase in risk for either premenopausal or postmenopausal breast cancer, the study found.

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Vivus, aiming at surgically menopausal women, found a 64% increase in "satisfying" sexual activity in a small trial of premenopausal women (placebo was 42%) and is now launching a larger late-stage test in postmenopausal women.

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