GNRH1 and endometriosis: In conclusion, for patients with stages I to II SUP-related infertility, several studies showed that laparoscopic excision or ablation of endometriosis lesions can improve their pregnancy outcomes.[5,6] However, long-acting GnRH-a down-regulation before FET did not significantly increase CPR and LBR, and did not reduce the miscarriage rate in patients with stages I to II SUP.