The Effect of Intrauterine Injection of Human Chorionic Gonadotrophin on Implantation Rate During ICSI Cycles: Systemic Review and Meta-Analysis

Abstract Background: Failed implantation is a major limiting factor in assisted reproduction. Therefore, a better understanding of the molecular mechanisms responsible for implantation may help clinicians to treat infertility and early pregnancy loss. Aim of Study: The aim of the present work was to perform a systemic review and meta-analysis to evaluate: The effects of intrauterine injection of the human chorionic gonadotrophin hormone and evaluate its significance prior to the embryo transfer. The effect of the different doses of human chorionic gonadotrophin (hCG) to be injected and their beneficial effects on the endometrial environment, implantation rate and preg-nancy rate in in vitro fertilization (IVF) outcomes. Subjects and Methods: We searched the PubMed, European clinical trial database (EuCLiD), Science direct (EMBASE), any randomized controlled trials (RCTs) that compared the intrauterine injection of HCG at the time of embryo transfer with nonintervention group were included, and data were extracted independently by two reviewers. The meta-analysis was performed by Revman 5.3 software. Eleven RCTs (3112 patients) were included in this meta-analysis. Results: PubMed: Searching strategy: [Human chorionic gonadotropin or human chorionic gonadotrophin (hCG)] or recombinant human chorionic gonadotrophin (hCG) or re-combinant human chorionic gonadotropin (r-hCG) and (in-trauterine or intrauterine injection or endometrial infusion) and (assisted reproductive techniques or ART or in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) or in vitro fertilization or intracytoplasmic sperm injections or embryo transfer). ScienceDirect (EMBASE): Searching strategy: [Human chorionic gonadotropin or human chorionic gonadotrophin (hCG)] and (intrauterine injection or endometrial infusion) and (assisted reproductive techniques or in vitro fertilization or intracytoplasmic sperm injections or embryo transfer). Filters: Medical journals only, open access, keyword in title "intrauterine". CENTRAL: Searching strategy: (Human chorionic gona-dotropin or human chorionic gonadotrophin (hCG) or recom-binant human chorionic gonadotrophin (hCG) or recombinant human chorionic gonadotropin (r-hCG)) and (intrauterine or intrauterine injection or endometrial infusion) and (assisted reproductive techniques or ART or in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) or in vitro fertili-zation or intracytoplasmic sperm injections or embryo transfer). Conclusion: Intrauterine injection of 500IU human cho-rionic gonadotrophin (hCG) at embryo transfer (ET) increases implantation and pregnancy rates. These findings suggest that intrauterine injection of human chorionic gonadotrophin (hCG) could be considered an adjuvant to traditional embryo transfer (ET) protocols