Vasectomy and Vasovasostomy - Reversal Surgery

In the case of vasectomy, the autoantibodies attack the sperm, and so are called antisperm antibodies. Such antibodies develop when sperm continue to be produced after vasectomy, but, instead of being confined to the reproductive passages, they leak out into the body. Once out of their natural habitat, the immune system perceives them as foreign invaders and develops antibodies to attack them.

Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.

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The antisperm antibodies bind to specific parts of the sperm (e.g., the head or tail) and cause problems depending on the site of attachment. Sperm may stick together (agglutinate), fail to interact with the woman''s cervix, or fail to penetrate the egg. Even after vasovasostomy, such antibodies often persist.

Oxidation. The immune factors that trigger the autoimmune process may have other harmful effects as well. In a process called oxidation, they can trigger the release of particles called free radicals, highly reactive oxygen molecules that, in excess, can do considerable damage to cells and genetic material. When high levels of free radicals persist after a vasectomy, they may, in theory at least, injure sperm DNA, contributing to infertility.

Reoperations After a Failed Vasovasostomy

Repeat Vasovasostomy. If pregnancy fails, in some cases a repeat vasovasostomy may be effective. Success rates depend on several factors:

The doctor''s skill.
Complications from the original operation.
Effects of anti-sperm antibodies.
Time elapsed since vasectomy (the shorter the better).
History of previous children. In one study, conception rates after reoperations were highest (80%) in couples who had had previous children. The pregnancy rate was only 17% when men had remarried.

A 2003 study indicated that the microscopic approach may be preferable for many repeat vasovasostomies.

Vasoepididymostomy. Vasoepididymostomy is a microsurgical technique that is useful when a vasovasostomy has failed because of damage to the epididymis. This procedure creates a bypass around the obstruction. It may be done on one or both sides of the testes.

To appreciate the difficulty of this operation, one should realize that the epididymis is 1/300th of an inch wide with a wall thickness of 1/1000th of an inch. Microscopic techniques are critical for the success of this procedure and require a surgeon who specializes in them. Refinements in vasoepididymostomy techniques are showing promising results, resulting in opened tubes in 77% to over 85% of cases.