Antibodies are proteins produced by the body and are used to identify substances that our body sees as strangers or foreign.
Sperm have a very important antigenicity, and not because they are protected in the testes, by a barrier called "blood-testis barrier" would be considered as foreign bodies in the body of man.
Anti Sperm Antibodies (ASA) occur when the blood-testis barrier is interrupted by an obstruction, infection or trauma.
The immunoglobulins (or antibodies) of the IgG class may be present in serum and semen joining sperm, inhibiting their functional abilities.
The presence of such antibodies is the main cause of immune sterility in man. His diagnosis is extremely important to determine the best treatment to use assisted reproduction.