<prompt> All are true regarding medical treatment of endometriosis except?Oral progestins cause decidualization of endometrial tissueInjectable progestagen is used once in 3 months in the management of pain of endometriosisLevonorgestrel releasing intrauterine system reduces dysmenorrhoea in endometriosisGestrinone is given orally 2.5 - 5 mg per day to induce endometrial atrophy  <response>: Gestrinone has a long half life. It is a 19-noestosterone derivative. It is given orally 2.5 to 5 mg twice weekly for 6 to 9 months. It has androgenic, antiprogestagenic, antioestrogenic and antigonadotrophic action. Ref : Shaws Textbook of Gynaecology 