#21 : Letrozole Can Be a Good Adjuvant for In Vitro Fertilization (IVF) Procedure in Patient with Ovarian Endometriosis

Background and Aims: To evaluation the pregnancy rate in IVF procedure with letrozole in patient with ovarian endometrioma.

Method: Prospective study performed by single physician at primary fertility center. From August 2016 to November 2019, 109 cycles of IVF were performed from couples who were diagnosed as endometrioma. 40 women were diagnosed during ovarian cystectomy, 69 were by transvaginal ultrasonography. In 64 cycles, gonadotrophic releasing hormone (GnRH) antagonist protocol was used, and in another 45 cycles, gonadotrophin releasing hormone agonist (GnRHa) protocol were applied. In every cycle, 10 mg of letrozole was added from the start of gonadotrophin till the end of ovarian stimulation.

Results: Women’s age was 36.10±3.67, and the number of their previous IVF cycle was 2.66±1.63. AMH was 2.30±2.31, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2) on the third day of menstruation were 9.40±5.26, 7.81±4.60 and 54.1±44.2. Start dosages and total dosages of recombinant FSH were 314.32±74.99 and 2541.37±992.77, and serum E2 and progesterone on trigger day were 1220.06±1072.49 and 0.92±0.79. The endometrial thickness was 9.20±1.46. The number of obtained oocytes was 9.05±5.94 and metaphase II(M2) oocytes were 6.71±4.12. 1.91±0.42 embryos were transferred to the uterine cavity and 2.68±2.58 surplus embryos were cryopreserved. Pregnancy rate was diagnosed if serum beta human chorionic gonadotrophin (hCG) level was above 5 ng/ml on 14^th day after oocyte retrieval, and the result was 44.95% (49/109). Clinical pregnancy rate which was defined if gestational sac was visualized by transvaginal ultrasonography after at least 21^st days after oocyte retrieval, and the result was 24.77% (27/109).

Conclusion: In IVF procedure for the patients with ovarian endometrioma, just adding letrozole to conventional controlled ovarian hyperstimulation protocol can reduce serum peak E2 level without make harmful effect on uterine endometrium, and result in comparable pregnancy rate.