Abstract: Objective: To observe the therapeutic effects and safety of endocrine response of gonadotropin（hormone）- releasing hormone-analogue （GnRHa） combined with conjugated estrogen （CEE） and medroxyprogesterone acetate （MPA） in the treatment of advanced endometriosis after laparoscopic operation. Methods: Ninety-six cases of endometriosis after laparoscopic. Patients were randomly divided into three groups， single-agent group（33 cases）: in postoperative subcutaneous injection of triptorelin 3.75 mg， once every 4 weeks for 6 times; anti-plus group（32 cases）: after subcutaneous injection of triptorelinin 3.75 mg， once every 4 weeks for 6 times， since the fourth injection， we add conjugated estrogens 0.625 mg/d with medroxyprogesterone acetate 5 mg/d for 3 months; the control group （31 cases） without drug treatment. Results: Complete remission rate of clinical symptoms in single-agent group and add-back group was 90.9% and 93.8% respectively， significantly higher than 48.4% in control group（P ＜0.01）；cumulative relapse rates in single-agent group and add-back group were 3.0% and 6.2%，significantly lower than 33.3% in the control group（P ＜0.01）；the serum E2，FSH，LH concentration in single-agent group after treatment was significantly lower than that before treatment（P ＜0.01）. Conclusions: GnRHa combined with conjugated estrogen and medroxyprogesterone acetate is safe and effective in the control of low estrogen symptoms， reduce bone turnover， etc. Add-back therapy can reduce the side effects of GnRHa with unaffectting its efficacy.

Key words: Laparoscopy, Endometriosis, Gonadotropin-releasing hormone, Triptorelin, Estrogens, Clinical protocols