Methods for treating or reducing the likelihood of acquiring estrogen -related (e.g. estrogen-exacerbated) diseases including endometriosis include administering to a patient a selective estrogen receptor modulator (SERM), in combination with inhibiting ovarian secretions, e.g., by administering an LHRH agonist or antagonist. In some embodiments, a precursor of sex steroids, said precursor being selected from the group consisting of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA- S), androst-5-ene-3β,17β-diol (5-diol), and androstenedione or a compound transformed into one of these, is also administered
