目的:研究GnRH-a长方案控制性超促排卵(COH)对小鼠妊娠率、胚胎着床率及着床期HOXA-10基因表达的影响,探讨COH影响胚胎着床的机制。方法:实验动物随机分为实验组(GnRH-a+hMG+hCG)和对照组(生理盐水),雌、雄合笼后观察小鼠阴栓率,于着床期取小鼠子宫,观察妊娠率及胚胎着床数,计算着床率;应用RT-PCR、Real-time PCR方法及免疫组织化学法分别检测小鼠着床期子宫内膜Hoxa-10 mRNA及蛋白的表达。结果:实验组小鼠阴栓率及妊娠率均明显低于对照组(P<0.01),实验组胚胎着床数高于对照组(P<0.01),但胚胎着床率较对照组显著降低(P<0.05),着床期小鼠子宫内膜Hoxa-10mRNA及蛋白表达下降,与对照组比较均有明显差异(P<0.05)。结论:GnRH-a长方案COH可引起小鼠着床期子宫内膜Hoxa-10表达下降,导致子宫内膜容受性降低,从而影响小鼠妊娠及胚胎着床。 Objective: To study the effect of GnRH-a long-term controlled ovarian hyperstimulation (COH) on pregnancy rate, embryo implantation rate and implantation HOXA-10 gene expression in mice, and explore the mechanism of COH affecting embryo implantation. Methods: The experimental animals were randomly divided into experimental group (GnRH-a + hMG + hCG) and control group (normal saline) The implantation rate and embryo implantation rate were calculated to calculate the implantation rate. The mRNA and protein expression of Hoxa-10 in implantation endometrium of mice were detected by RT-PCR, Real-time PCR and immunohistochemistry respectively. Results: The mice’s vaginal plug rate and pregnancy rate in the experimental group were significantly lower than those in the control group (P <0.01). The embryo implantation number in the experimental group was higher than that in the control group (P <0.01), but the embryo implantation rate was significantly lower than that in the control group (P <0.05). The mRNA and protein expression of Hoxa-10 in endometrium of implantation mice decreased significantly compared with the control group (P <0.05). Conclusion: GnRH-a long-term COH can reduce the expression of Hoxa-10 in implantation endometrium of mice, leading to the decrease of endometrial receptivity, thus affecting the pregnancy and embryo implantation.