Abstract: Objective To investigate the efficacy of letrozole co-treatment with antagonist protocol in poor ovarian response (POR) patients under in-vitro fertilization treatment. Methods Twenty-six patients diagnosed with POR at POSEIDON criterion group 3 and 4 in Dongguan Maternal and Child Health Hospital from October 2019 to October 2020 were divided into two groups with the random number table method. The letrozole group was (35.69±4.25) years old with a body mass index (BMI) of (21.21±2.50) kg/m2 ; the control group was (33.15±4.02) years old with a BMI of (21.35±2.16) kg/m2 . The 13 patients in the letrozole group received letrozole 5 mg/d combined with gonadotropin (Gn) (300 U/d) for ovulation induction from the second day of menstrual cycle to night acupuncture day; the 13 patients in the control group received Gn (300 U/d) for ovulation induction from the second day of menstrual cycle to night acupuncture day. In both groups, serum luteinizing hormone (LH), estradiol (E2), and maximal follicular meridian were observed during the process of ovulation induction, adding 0.25 mg/d of cetrorelix acetate powder for injection as antagonist until night acupuncture day as appropriate. After Gn initiation, follicular development and sex hormone changes were monitored by B ultrasound in both groups. When follicles matured, 10 000 U of human chorionic gonadotropin (HCG) was intramuscularly injected, and the oocytes were harvested at 36 h. The total amount of Gn, number of oocytes harvested, number of available embryos, fertilization rate, fresh embryo transplantation rate, and clinical pregnancy rate were compared between the two groups. Independent sample t test was used for measurement data and Fisher exact probability method for count data. Results The total amount of Gn and the number of oocytes harvested in the letrozole group and the control group were (2 930.77±809.78) U, (6.69±3.52), and (2 838.46±538.96) U, (4.92±2.87), respectively, with no statistically significant differences (both P>0.05); the number of available embryos in the letrozole group [(3.00±1.41)] was higher than that in the control group [(1.77±1.01)], with a statistically significant difference (P<0.05). The fertilization rates of the two groups were (82.29±18.74)% and (78.76±26.83)%, respectively, with no statistically significant difference (P>0.05). The fresh embryo transplantation rate of the letrozole group [69.23% (9/13)] was higher than that of the control group [23.08% (3/13)], with a statistically significant difference (P<0.05); the clinical pregnancy rate of the letrozole group [66.67% (6/9)] was higher than that of the control group [33.33% (1/3)], with no statistically significant difference (P>0.05). Conclusion In PORs, the number of oocytes harvested, available embryos, and fresh embryo transplantation rate are significantly increased by letrozole co-treatment during the entire stimulation course.

Key words: Poor ovarian response, In-vitro fertilization, Letrozole, Antagonist protocol, Gonadotropin

摘要： 目的 观察来曲唑联合拮抗剂方案应用于卵巢储备功能低下患者体外受精（in vitro fertilization，IVF）助孕的疗效。方法 将 2019 年 10 月至 2020年10月期间在东莞市妇幼保健院的波塞冬标准 3、4 组的卵巢储备功能低下的26例患者应用随机数字表法分为2组。来曲唑组年龄（35.69±4.25）岁，体质量指数（BMI）（21.21±2.50）kg/m2 ；对照组年龄（33.15±4.02）岁，BMI （21.35±2.16）kg/m2 。 来曲唑组13例月经周期第2天始来曲唑 5 mg/d 口服联合促性腺激素 （gonadotropin，Gn）促排卵（300 U/d）至夜针日；对照组13例月经周期第2天开始每天予Gn（300 U/d）促排卵至夜针日。两组均在促排过程中综合血清促黄体生成素（luteinizing hormone，LH）、雌二醇 （estradiol，E2）值及最大卵泡经线酌情加拮抗剂注射用醋酸西曲瑞克 0.25 mg/d 直至夜针日；均在 Gn 启动后 B 超监测卵泡发育和检测性激素变化，待卵泡成熟时予绒促性腺激素（human chorionic gonadotropin，HCG）10 000 U肌注，36 h取卵。对比两组患者的 Gn总量、获卵数、可利用胚胎数、受精率及鲜胚移植率、临床妊娠率。计量资料行独立样本 t 检验，计数资料行 Fisher 确切概率法。结果 来曲唑组和对照组的Gn总量、获卵数分别为（2 930.77±809.78）U、（6.69±3.52）枚和（2 838.46±538.96） U、（4.92±2.87）枚，差异均无统计学意义（均P>0.05）；来曲唑组的可利用胚胎数（3.00±1.41）枚，较对照组的（1.77±1.01）高，差异有统计学意义（P<0.05）。两组的受精率分别为（82.29±18.74）%和（78.76± 26.83）%，差异无统计学意义（P>0.05）；来曲唑组鲜胚移植率［69.23%（9/13）］较对照组的［23.08%（3/ 13）］高，差异有统计学意义（P<0.05），来曲唑组的临床妊娠率［66.67%（6/9）］较对照组［33.33%（1/3）］ 高，但差异无统计学意义（P>0.05）。结论 卵巢储备功能低下的患者在拮抗剂方案促排过程中加用来曲唑能提高获卵数、可利用胚胎数、鲜胚移植率。

关键词: 卵巢低反应, 人工授精胚胎移植术, 来曲唑, 拮抗剂方案, 促性腺激素