Intrauterine administration of peripheral blood mononuclear cells activated by human chorionic gonadotropin in patients with repeated implantation failure: A meta-analysis

•Patients with RIF benefited by intrauterine administration of hCG-activated PBMCs prior to ET.•Reproductive outcomes were improved when PBMCs were cultured with hCG for 48 h.•Clinical outcomes were improved when PBMCs injection was administered two or three days before ET.•hCG dosage and PBMCs concentration did not evidently affect the therapeutic efficiency.