Correlations between results of the immunobead test and the sperm penetration assay

Immunobead testing (IBT) and human sperm-hamster egg penetration assay (SPA) were performed in 233 infertile men. Positive immunologic results were recorded in 31 (13.3%). Significant reduction in SPA scores was found in patients with IgG antisperm antibodies alone but not in patients with IgA alone or in combination with IgG. Normal SPA scores were seen in 56% of immunonegative patients (n = 113) vs. 32% of immunopositive patients (n = 10). Therefore, a normal SPA does not rule out the presence of significant levels of antisperm antibodies.