I. Causes of Anti-Sperm Antibodies (AsAb): 1. Infection of the reproductive system: epididymitis 2. Obstruction of the vas deferens 3. Trauma to the contents of the scrotum: trauma to the testes, epididymis, vas deferens, and after vasectomy/resection 2. Mechanism of production – Any cause of blood-testis and blood-epididymis barrier destruction, sperm as antigen into the blood circulation, will stimulate the immune system response The anti-sperm antibodies are produced. 1, AsAb exists in serum, seminal plasma, cervical mucus and other body fluids, human anti-sperm antibodies mainly have three subtypes: IgG, IgA, IgM 2, the body receives sperm antigen stimulation at the earliest to produce immunoglobulin IgM, disappears in a few weeks, replaced by the long-term presence of IgG, AsAb positive men, IgG rarely appear alone, generally appear at the same time IgG, IgA 3, IgG are circulating/braking antibodies, mainly present in serum, and IgA are local/agglutinating antibodies, mainly present in semen. IgA, when combined with sperm, greatly reduces the ability of sperm to penetrate cervical mucus, whereas IgG does not have this effect. Dozens of laboratories have reported the presence of sperm agglutination antibody IgA and sperm braking antibody IgG in the sera of approximately 50% of recipients. antibodies can be detected 7-14 days after surgery, and the positive rate and antibody titer increase significantly after six months. The effect of AsAb on testicular spermatogenesis: Clinically, it has long been found that when reperfusion is performed after ligation, the success rate of surgery is 50% to 70%, but the conception rate is only 25%, which is consistent with the success of surgery but low conception rate after reperfusion in obstructive azoospermia. It is speculated that this may be related to the immune response. Vasectomy reversal also produces AsAb, which persists 2 years after reversal, and the antibody positivity rate does not change with longer reversal time. The mechanism of action of AsAb leading to male immune infertility is 1) to prevent sperm from crossing the cervical mucus and interfere with sperm capacitation 2) to affect the viability of sperm by agglutination and braking 3) to inhibit the release of sperm acrosome enzymes or reduce the activity of acrosome enzymes, affecting the ability of sperm to fertilize 4) to affect sperm-egg fusion and interfere with the development of fertilized eggs 5) to affect the development of the billet by anti-sperm cytotoxic effects, or even to cause the cessation of billet development and It may even lead to abortion.