Identification of antisperm antibodies on sperm of infertile men.

An indirect radiolabeled antiglobulin test for plasma antisperm antibodies was modified so that sperm-associated antibodies could be identified. Ten of 16 (63%) infertile men with plasma IgG antisperm antibodies were found to have an elevated sperm-associated IgG. Two of these men with an elevated sperm-associated IgG also had an elevated sperm-associated IGA; one other man with plasma IgG antisperm antibodies, but no detectable sperm-associated IgG, was noted to have an elevated sperm-associated IgA. Eighteen infertile men with a history that suggested antibody-mediated infertility did not have plasma IgG antisperm antibodies; one (6%) of these men was found to have an elevated sperm-associated IgG; none of these 18 men were found to have an elevated sperm-associated IgA. No patient was found to have sperm-associated IgM.