Varicocele-related infertility is not associated with increased sperm-bound antibody

Immunological factors have been implicated as a cause of unexplained infertility. Previous studies have demonstrated increased levels of sperm-bound antibody in infertile men with varicoceles and have postulated their role in varicocele-related infertility. However, these studies were performed using an enzyme-linked immunosorbent assay. We evaluated retrospectively 111 male patients referred for infertility using a direct immunobead assay. Of the patients 29 had grade II or III varicoceles (that is palpable or easily visualized) and 82 were without varicocele. Four patients who had undergone vasovasostomy were included as controls for the assay. A direct immunobead assay was performed for isotype IgG and IgA sperm-bound antibody using a standard protocol. A computerized semen analysis was also performed. Greater than 20% binding, excluding tail tip activity, was considered significant. Of 29 patients with and 82 without a varicocele significant binding was identified in 5 (17%) and 9 (11%), respectively. Chi-square statistical analysis did not reveal this difference to be significant (p < 0.05). All 4 vasovasostomy patients demonstrated significant binding. We conclude from this study that infertile men with varicoceles do not demonstrate significantly increased levels of sperm-bound antibody compared to infertile controls and, therefore, sperm-bound antibody does not appear to have a significant role in varicocele-related infertility.