 As such, ethisterone does not appear to share the estrogenic activity of norethisterone, at least in humans.Aside from ethinylestradiol, 17α-ethynyl-3α-androstanediol and 17α-ethynyl-3β-androstanediol may be estrogenic metabolites of ethisterone.Ethisterone is active both orally and sublingually in humans.