Anti-sperm antibodies and reproductive failures

Reproductive failures include infertility and recurrent pregnancy loss (RPL). Although the relative importance of immunological factors in human reproduction remains unclear, there may be immune-mediated reproductive failures in a portion of unexplained infertility and RPL. As a cause of immunological factor, anti-sperm antibodies (ASA) are produced both in men and women. There have been reported several antigens in the surface of sperm that are especially foreign to women. The presence of ASA, especially sperm-immobilizing antibodies, in the sera of infertile women has been shown to inhibit sperm migration in the female genital tract. Therefore, the effectiveness of the treatments for infertile women with sperm-immobilizing antibodies by timed intercourse or intra-uterine insemination is limited. Such antibodies can also exert inhibitory effects on various stages of sperm-egg interaction and subsequent embryo development in vitro. It is suggested that ASA testing for infertile women should be performed before proceeding IVF. The manipulation of gametes and embryos from patients having sperm-immobilizing antibodies should be carefully carried out especially to avoid contaminating patient's serum and follicular fluid in the culture medium in order to overcome the immunological causes of female infertility by ASA, and satisfactory results under suitable conditions for gametes and embryos have been obtained. The relationship between ASA and RPL was controversially reported. Increased miscarriage rates in women with ASA were demonstrated by some authors. In contrast, lack of association between ASA and RPL was reported. In this manuscript, we are focusing the roles of ASA in women with reproductive failures.