 OUTLINE: This is a randomized, placebo-controlled, double-blind study. Patients are stratified according to planned tamoxifen therapy yes vs no vs undecided, planned taxane therapy yes vs no vs undecided, time from last menses 1-3 months vs longer than 3 months to 6 months, and age under 40 vs 40 to 49 vs 50 and over. Patients are randomized to 1 of 2 treatment arms. In both arms, treatment begins during the first month of chemotherapy and continues for 1 year in the absence of unacceptable toxicity. For more information regarding the treatment arms, please see the Arms section below. Questionnaires about cessation of menses, ovarian failure, and menopausal symptoms are completed at baseline, monthly during chemotherapy, at 6 months, and then at 1 and 2 years. 