The poor prognostic value of low to moderate levels of sperm surface-bound antibodies

The clinical significance of antisperm antibodies for fertility remains controversial. In this study, we determined whether the presence, isotype, region and/or amount of sperm-bound antibody was of any predictive value for future fertility in 534 men using Cox's proportional hazards model. Significant correlations between the presence of antibodies and semen parameters were recorded, such as sperm mucus penetration and sperm motility. However, low (less than 10%) negative binding and moderate (less than 50%) binding had no significant effect on the probability of conception or the time to conception. This study confirms in-vitro data suggesting that sperm function is not impaired unless the degree of antibody binding to spermatozoa is very high.