目的:探讨长效促性腺激素释放激素激动剂(GnRH-a)降调节后促性腺激素(Gn)的启动时机对体外受精/卵胞质内单精子注射-胚胎移植(IVF/ICSI-ET)结局的影响。方法:对接受IVF/ICSI-ET治疗的710个新鲜周期进行回顾性分析,根据GnRH-a降调节时间分组:14~15 d者为A组,16~17 d者为B组,≥18 d者为C组。分析和比较3组在年龄、不育年限、Gn使用天数、Gn使用剂量、启动日血清卵泡刺激素(FSH)、黄体生成素(LH)、雌激素(E2)水平、hCG注射日内膜厚度、获卵数、可移植胚胎数、种植率、临床妊娠率、流产率的差异。另根据月经周期Gn启动时间分组:在月经周期第3~7日者为Ⅰ组,月经第8日及以后者为Ⅱ组。分析和比较组间上述临床指标的差异。结果:A组的Gn用量为32.4±11.4支,Gn使用天数为12.5±1.9 d,显著大于B组(30.9±11.6支;10.8±2.5 d)、C组(30.5±11.5支;10.8±2.3 d),差异有统计学意义(P均<0.05)。但Gn用量、Gn使用天数B组与C组间无统计学差异(P均>0.05)。Gn不同启动时间的3组间在种植率、临床妊娠率及流产率方面无统计学差异(P均>0.05);Ⅰ组、Ⅱ组的种植率、临床妊娠率、流产率相比较,差异亦无统计学意义(P均>0.05)。结论:适当延长GnRH-a降调节天数有利于降低Gn用药剂量及用药时间,但是Gn启动时间对临床结局无显著影响。 OBJECTIVE: To investigate the effect of GnRH promoter on the in vitro fertilization / intracytoplasmic sperm injection-embryo transfer (IVF / ICSI-ET) outcome of GnRH-a Impact. Methods: A total of 710 fresh cycles treated with IVF / ICSI-ET were retrospectively analyzed. According to the time of GnRH-a down regulation, group A was 14-15 days, group B was 16-17 days, group B was ≥18 days For the C group. The age, the number of days of infertility, the number of days of Gn use, the dosage of Gn, the level of serum FSH, LH and E2, the thickness of endometrium on day of hCG injection were analyzed and compared. , Number of oocytes retrieved, number of transplantable embryos, implantation rate, clinical pregnancy rate and abortion rate. Another according to the menstrual cycle Gn start time grouping: in the menstrual cycle from the 3rd to the 7th for group Ⅰ, on the 8th and later menstruation group Ⅱ. Analyze and compare the difference between the above clinical indexes. Results: The amount of Gn in group A was 32.4 ± 11.4 and that of Gn was 12.5 ± 1.9 d in group A, which was significantly higher than that in group B (30.9 ± 11.6 and 10.8 ± 2.5 d), in group C (30.5 ± 11.5 and 10.8 ± 2.3 d ), The difference was statistically significant (P <0.05). However, there was no significant difference in the amount of Gn and days of Gn between group B and group C (all P> 0.05). There was no significant difference in implantation rate, clinical pregnancy rate and miscarriage rate among the three groups with different Gn activation time (P> 0.05). The differences in implantation rate, clinical pregnancy rate and abortion rate between Ⅰ group and Ⅱ group were also significant No statistical significance (P> 0.05). CONCLUSION: Appropriately prolonging the days of GnRH-a down regulation is beneficial to reduce the dosage of Gn and the time of medication, but the Gn activation time has no significant effect on the clinical outcome.