Tibolone, also known as 7α-methylnoretynodrel, as well as 7α-methyl-17α-ethynyl-19-nor-δ 5(10) -testosterone or as 7α-methyl-17α-ethynylestr-5(10)-en-17β-ol-3-one, is a synthetic estrane steroid and a derivative of testosterone and 19-nortestosterone .   It is more specifically a derivative of norethisterone (17α-ethynyl-19-nortestosterone) and is a member of the estrane subgroup of the 19-nortestosterone family of progestins.     Tibolone is the 7α-methyl derivative of the progestin noretynodrel (17α-ethynyl-δ 5(10) -19-nortestosterone).  Other steroids related to tibolone include the progestin norgesterone (17α-vinyl-δ 5(10) -19-nortestosterone) and the anabolic steroids trestolone (7α-methyl-19-nortestosterone) and mibolerone (7α,17α-dimethyl-19-nortestosterone). 
However, in December 2004 the United States the 14-member Food and Drug Administration (FDA) advisory committee, plus voting consultants, for Reproductive Health Drugs unanimously rejected Procter and Gamble's fast-track request for Intrinsa citing concerns about off-label use . In Canada, post-menopausal women have been able to obtain government-approved testosterone treatment since 2002. In Australia, post-menopausal women can use Organon testosterone implants which have to be surgically inserted and last from three to six months.