植入失败已经成为限制辅助生殖不孕症治疗成功的主要因素，而临床证据表明，接受促排卵治疗患者，HCG日孕酮水平过高会显著降低临床妊娠率，导致植入失败，更重要的是这部分患者占据整个接受促排卵治疗的患者人数的35%。尽管如此，对于这种HCG日高孕酮影响临床妊娠率的分子机制还不清楚。本研究拟利用前期研究筛选的HCG日高孕酮水平患者子宫内膜特异表达的4个microRNA，通过生物信息学方法筛选重要的靶基因，并在体外细胞水平与动物模型中进行进一步鉴定，研究这些基因在HCG日高孕酮水平患者中的作用，从而明确这部分基因是由于促排卵诱导发生表达差异的，还是在这部分患者本身就存在的。通过本研究，可以深入探索HCG日高孕酮与临床妊娠之间的分子调控机制，进而对该重要临床问题解决方案的提出提供理论依据，对于后续继续探讨激素调控改善辅助生殖成功率具有重要的价值和意义。

Implantation failure limited the development of assisted reproductive technology and the success of infertility treatment. The clinical data showed that higher progesterone concentration at HCG priming day in the serum of the superovulated women would affect the clinical pregnancy and IVF outcome, and moreover the ratio of these women was 35% of total women within the superovulated cycles. In spit of an important clinical issue, there are few of studies to discuss the potential molecular mechanism. In the present study, we focused on the 4 microRNAs identified by microRNA chip experiments between the endometrium samples from women with normal progesterone concentration and higher progesterone concentration at HCG priming day, and screened the target genes regulated by these 4 microRNAs. Furthermore these genes will be identified the functions in vitro and in vivo using the cell culture models and animal models, respectively. Finally these genes would be divided into two parts following the study results, one of them were differentiated expressed in these patients themselves, and the other part of them were differentiated expressed in the procedure of superovulation. In conclusion, the present study would discuss the molecular regulation mechanism between higher progesterone concentration at HCG priming day and the subsequent clinical pregnancy, and provided the academic proof for the solution of this clinical issue, and facilitate the study of the relation between hormones regulation and embryo implantation.