I-40: Implantation Failure

Background: The process of implantation involves the interaction of the human embryo and the uterine epithelium. Failure of implantation is a major reason for infertility in women and the inability to achieve endometrial receptivity is responsible for much of the failure of reproductive technologies. Management of repeated implantation failure despite transfer of good-quality embryos still remains a dilemma for ART specialists. The aim of this review is to evaluate the different aspects of implantation failure investigation and management. Materials and Methods: Pubmed, Medline, Cochraneresearch Results: Several factors, including embryo quality, and cellular and molecular changes in endometrium may contribute to the insufficient feto-maternal interaction resulting in reproductive failure. Genetic or metabolic abnormalities of the embryo are very important in preventing of implantation and embryonic growth. The efficacy of preimplantation genetic screening (PGS) in repeated IVF failure is questionable but the studies suggest that young patients with RIF may not benefit from PGS. Local and systemic immune factors, cytokines, and growth factors may interact with adhesion molecules. So, heparin and aspirin can overcome the antibodies such as APA , AEA (anti endometrial antibodies) effects and other matrix-associated proteins, glycoproteins, and peptides. Although, leukemia inhibitory factor (LIF) is an important factor in the human implantation process but the recombinant LIF was not associated with higher pregnancy rate. Recently, it was found that the injury-derived inflammation in the biopsy-treated patients provokes the immune system to generate an inflammatory reaction and generates a focus for uterine dendritic cells accumulation that, in turn, enhances the endometrial expression of essential molecules, which facilitate the interaction between the embryo and the uterine epithelium.Conclusion: A better understanding of the mechanisms underlying endometrial receptivity and implantation should guide clinicians through proper management and treatment of infertility and implantation failure, and may eventually enable widespread adherence to single embryo transfer practices.