Effects of Tibolone on the Endometrium in Postmenopausal Women

This study focuses on the effects of a medication called Tibolone on the endometrium, the lining of the uterus. Postmenopausal women often experience symptoms like hot flashes and bone loss due to a deficiency in estrogen. While estrogen treatment can help, it can also increase the risk of endometrial hyperplasia, a thickening of the endometrium that can lead to cancer. Tibolone is a unique compound that treats menopause symptoms and prevents bone loss without stimulating the endometrium like estrogens do. It's converted in the body into metabolites with estrogenic, progestagenic, and androgenic effects. The goal of this study is to understand Tibolone's effects on the endometrium, as it has been observed to cause a slight increase in thickness after long-term use, although hyperplasia rarely occurs. In this clinical trial, postmenopausal women undergoing vaginal hysterectomy for prolapse treatment are assigned to one of four groups: no hormonal treatment, Tibolone treatment, estrogen-only treatment, or estrogen plus progestagen treatment. The treatments are administered orally for 21 days prior to surgery. The investigators are blinded to the patient treatments during the analysis. The study measures the effects of Tibolone on the endometrium by evaluating hormone levels, histology, and gene expression in the endometrium and sera. The primary outcomes include biochemical evaluation of uterine tissue and sera, histologic evaluation of the endometrium, and molecular assessment of gene expression.