We studied whether the spermatozoa from sperm autoimmune infertile men undergo premature acrosomal loss and whether this relates to the presence of sperm antibodies in wives.We evaluated acrosome status of live washed native and overnight capacitated spermatozoa from 17 sperm nonautoimmune fertile and 23 sperm autoimmune infertile men using an immunofluorescent peanut lectin binding assay. We used cytotoxic and immunobead binding assays to prescreen the serum and seminal plasma of these men, and serum and cervical mucus of the wives for immunological infertility. We performed immunofluorescent sperm antibody assays on all study samples to ascertain sperm antibody isotype levels in each sample. Levels of acrosomal loss in husband native and capacitated spermatozoa were correlated with levels of IgG, IgA and IgM sperm antibodies in the study samples.Sperm autoimmune infertile men had a significantly larger percentage of sperm (p <0.0001) that had lost the acrosome and a lower percentage of sperm with intact acrosome (p <0.0001) in native and capacitated preparations in contrast to those of fertile controls. Levels of cytotoxic and IgA antibodies, especially in seminal plasma and cervical mucus, correlated significantly with percentages of sperm with a total loss of acrosome in native and capacitated sperm preparations (p < or = 0.01).Infertile men with sperm antibodies in serum and seminal plasma undergo premature acrosome loss. This loss may expose the reproductive tract immune system, especially that involving IgA, in autoimmune infertile men and the wives to high immunogenic levels of sperm acrosome membrane antigens, thereby rendering them immunologically infertile.