 Tibolone, a tissue-selective compound with a combination of estrogenic, progestogenic and androgenic properties, is used as an alternative for estrogen or estrogen plus progesterone hormone therapy for the treatment of symptoms associated with menopause and osteoporosis. The current study compares endometrial histology, biochemistry hormone levels and gene-expression profiles after short-term 21-days treatment with tibolone, to the findings after treatment with estradiol-only E2 and E2Medroxyprogesterone Acetate MPA in healthy postmenopausal women undergoing hysterectomy for endometrial prolaps. 