Ejaculates from infertile men with significant levels of antisperm antibodies were processed in vitro, in an attempt to prepare sub-populations of antibody-free spermatozoa. Semen samples were processed on a discontinuous Percoll gradient and the resultant sperm preparation was treated with immunobeads. Selection of antibody-free spermatozoa was achieved: less than 10% of the resulting spermatozoa showed binding to immunobeads after treatment in all cases investigated. The overnight survival of these antibody-free spermatozoa was comparable to, or better than, that of the untreated antibody-coated sample obtained from the Percoll gradient. The fertility potential of these treated spermatozoa is currently under investigation.