Can vagifem (10mcg) raise your cancer risk if taken before menopause? packet insert says only to be used after menopause.

No: There is no evidence that the use of estrogen prior to menopause can initiate cancer. If a patient has an undetected early malignancy of the breast then small doses of vaginal estrogen may to a minor degree stimulate those cells. The same thing holds true for tamoxifen which when used as an antiestrogen has estrogenic activity on the lining of the uterus and may help Ca formation.