Effect of Intrauterine Injection of HCG on Clinical Pregnancy Outcome in Repeated Implantation Failure Patients

we will use the catheter to pass through the cervix, and after that, the experiment Group will accept 40 μl 500 IU HCG injection into the uterine cavity 2 days before the blastocyst transfer.

The placebo group will accept 40 μl of culture medium injection into the uterine cavity 2 days before the blastocyst transfer.