Is there a role of autoimmunity in implantation failure after in-vitro fertilization?

PURPOSE OF REVIEW: The process of implantation involves the interaction of the human blastocyst and the uterine epithelium. Several autoimmune factors have been implicated to have an influence on implantation failure. RECENT FINDINGS: Recent studies have investigated the role of autoimmune factors in implantation in women undergoing in-vitro fertilization. Antiphospholipid antibodies are identified more frequently in women undergoing in-vitro fertilization, but their presence does not appear to influence the outcome of pregnancy, miscarriage, or live birth rates. Antithyroid antibodies are commonly found in women of reproductive age, but implantation rates and miscarriage rates are not altered when women have normal thyroid function. Antinuclear antibodies may be a marker for underlying autoimmune disease when coupled with certain signs and symptoms, but low-titer antibodies do not influence in-vitro fertilization outcome. Antisperm antibodies are more often associated with fertilization failure when found in high titers in seminal plasma, in sperm, or in the mucosal immune system of women. Antisperm antibodies are uncommon but most often associated with ovarian hypofunction. SUMMARY: Implantation is characterized by the interaction of two immunologically and genetically distinct tissues. During implantation, local and systemic immune factors, cytokines, and growth factors may interact with adhesion molecules and other matrix-associated proteins, glycoproteins, and peptides.