Initially, written and informed consent will be received from people with RIF referred to the Tabriz Center for Infertility, who are our target population in this project . To start the study using the antagonist protocol, when the follicle reaches a diameter of 14 mm, the GnRH antagonist is injected subcutaneously. After seeing the 17 mm follicle, HCG is injected muscle. After that, oocyte is removed and IVF is done. After these steps, PBMCs should be collected from peripheral blood. For this purpose, on the day of ovulation induction, blood samples are taken from patients with RIF and stored in citrate tubes. Then, the PBMC separates with the ficus. After isolating and cultivating these cells, they are injected into the endometrium two days before embryo transfer (ET). The flow cytometry technique will then be used to count the number of Th1 and Th2 cells. Ultimately, after this period, the patient will be evaluated in terms of pregnancy by laboratory method and βhCG protein assay and by ELISA technique. The rate of fetal implantation is also measured by gestational sac and ultrasound. To monitor the number of newborns born by RIF people, we will continue to monitor patients with their βhCG test after positive treatment with obstetric and gynecologic doctors. After about 9 months, we will evaluate the number of newborns born by the subjects and compare them to the control group who received no treatment.