Frequently Asked Questions (FAQs)
An anti-sperm antibody is defined as an immunoglobulin with antibody activity against a sperm antigen that plays a role in fertility, since not every antibody that binds to the sperm surface influences sperm function. Sperm antibodies are associated with some cases of infertility. In couples with abnormal post-coital tests, 24% males and 35% females exhibit sperm antibodies. These antibodies interfere with the binding of the sperm head to the zonapellucida of the egg. Sperm antibody binding to head or tail antigens is considered specific for immunologic infertility. These antibodies can be produced in both males and females, therefore affecting their fertility. Spermatozoa are separated from the immune system in men by the blood-testicular barrier. This barrier is breached in conditions like vasectomy, repeated infections, obstruction of the ducts, cryptorchidism, varicocele, trauma torsion, and genetic predisposition, leading to the development of anti-sperm antibodies. In women, non-specific bacterial or viral infections produce antibodies that cross-react with spermatozoan antigens. These antibodies affect sperm motility penetration through cervical mucous attachment of the sperm to the oocyte and actual sperm penetration and fertilization of the oocyte. The possibility of an autoimmune process in the development of sperm antibodies has also been considered.