Sperm Autoantibodies

Clinically, antibodies against sperm are found in 3% to 12% of men who undergo evaluation for infertility and can be found in the serum, seminal plasma or sperm-bound. As antibodies in the serum cannot logistically bind to sperm unless they transudate into semen, these immunoglobulins are considered clinically less important than sperm-bound antibodies. The presence of anti-sperm antibodies in infertile men was first reported in 1954 by Rumke and Wilson. Anti sperm antigen has been described as three immunoglobulin isotopes (IgG, IgA, IgM) each of which targets different part of the spermatozoa. If more than 10% of the sperm are bound to antisperm antibodies (ASA), then infertility is suspected.