Tibolone is an estrogen-like compound used for the treatment of the symptoms associated with menopausal transition (i.e., climacteric symptoms) and also for the treatment of osteoporosis.{12450} Three major metabolites of tibolone are responsible for its tissue selective mechanism of action. Conversion into 3α- and 3β-hydroxy-tibolone results in estrogenic effects in brain, vagina, and bone. The .DELTA.4 isomer has progestrogenic and androgenic effects and does not cause estrogenic stimulation in the endometrium.{12450} A two-year longitudinal study indicates that low doses (1.25-2.5 mg) of tibolone effectively relieve climacteric symptoms and prevent loss of bone mass in early postmenopausal women.{12449}