Eftekhar Maryam, Saeed Lida
Research and Clinical Center for Infertility, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Afzalipour Hospital, Kerman University of Medical Science, Kerman, Iran.
Int J Reprod Biomed. 2020 Apr 30;18(4):287-294. doi: 10.18502/ijrm.v13i4.6891. eCollection 2020 Apr.
Aromatase inhibitors prevent the aromatization of androgens into estrogens, which reduces the negative feedback of estrogen on the hypothalamic-pituitary axis. It is clear that increasing the secretion of follicle-stimulating hormones results in an increased follicular growth.
This study aimed to evaluate the effect of adding letrozole to gonadotropin on in vitro fertilization outcomes in normal responders.
In this randomized clinical trial, 100 normal responder women candidate for controlled ovarian stimulation were randomly enrolled in two groups (n = 50/each). In the case group letrozole was added to gonadotropin in the antagonist protocol. The control group received the conventional antagonist protocol. The main outcome was clinical and chemical pregnancy; and the second outcomes were the number of mature oocytes, the fertilization rate, estradiol level, and the total dose of gonadotropins.
Basic clinical and demographic features were comparable between the groups. Estradiol level on the day of human-chorionic-gonadotropin administration and the total gonadotropin consumption were significantly higher in the control group than the case group (p = 0.045). In addition, the number of MII oocytes was higher (but not significantl) in the case group than the control group (p = 0.09). Moreover, the endometrial thickness was significantly lower in the case group. There were no significant differences in fertilization rate and chemical and clinical pregnancy rates between the two groups.
Although adding letrozole to gonadotropin in normal responders reduces the total dose of gonadotropin, it does not improve the pregnancy outcomes.
芳香化酶抑制剂可阻止雄激素转化为雌激素，从而减少雌激素对下丘脑 - 垂体轴的负反馈。显然，促卵泡生成素分泌增加会导致卵泡生长加快。
本研究旨在评估在正常反应者中，来曲唑联合促性腺激素对体外受精结局的影响。
在这项随机临床试验中，100名接受控制性卵巢刺激的正常反应者女性被随机分为两组（每组n = 50）。病例组在拮抗剂方案中，促性腺激素添加来曲唑。对照组采用传统拮抗剂方案。主要结局为临床妊娠和生化妊娠；次要结局为成熟卵母细胞数量、受精率、雌二醇水平和促性腺激素总剂量。
两组之间的基本临床和人口统计学特征具有可比性。对照组在注射人绒毛膜促性腺激素当天的雌二醇水平和促性腺激素总消耗量显著高于病例组（p = 0.045）。此外，病例组的MII卵母细胞数量高于对照组（但无显著差异）（p = 0.09）。而且，病例组的子宫内膜厚度显著更低。两组之间的受精率、生化妊娠率和临床妊娠率无显著差异。
虽然在正常反应者中，促性腺激素添加来曲唑可降低促性腺激素总剂量，但并不能改善妊娠结局。
