Vasectomy reversal is a term used for surgical procedures that reconnect the male reproductive tract after interruption by a vasectomy. Two procedures are possible at the time of vasectomy reversal: vasovasostomy (vas deferens to vas deferens connection) and vasoepididymostomy (epididymis to vas deferens connection). Although vasectomy is considered a permanent form of contraception, advances in microsurgery have improved the success of vasectomy reversal procedures. The procedures remain technically demanding and expensive, and often do not restore the pre-vasectomy condition.
History
Technical advances in vasectomy reversal mirror those in microsurgery over the past 100 years. As a discipline, microsurgery was first performed by Carl Nylen in Sweden for middle ear surgery in 1910[1], but grew most rapidly as a discipline in the 20th century stimulated by its success in microvascular reconstruction of war-injured soldiers. The first microsurgical vasectomy reversal was performed by Earl Owen in 1971.
Prevalence
Vasectomy is a common method of contraception worldwide, with an estimated 40-60 million individuals having the procedure and 5-10% of couples choosing it as a birth control method[3]. In the U.S., about 5% of men who have had a vasectomy will change their minds and have a vasectomy reversal afterwards. The most common reason for a reversal is remarriage and a desire for more children. Other men in long-standing relationships have changed their minds and would like more children. There are occasional unfortunate individuals who have lost children and want to have more children. Lastly, vasectomy reversals are also performed to relieve post-vasectomy pain syndrome.
Biological considerations
Sperm are produced in the male sex gland or testicle. From there they travel through tubes (efferent tubules), exit the testes and enter a “storage site” or epididymis. The epididymis is essentially a single, 18-foot-long (5.5 m), tightly coiled, small tube, within which sperm mature to the point where they can move, swim and fertilize eggs. Testicular sperm are not able to fertilize eggs naturally (but can if they are injected directly into the egg in the laboratory), as this is learned in the epididymis. From the epididymis, a 14-inch, 3 mm-thick muscular tube called the vas deferens carries the sperm to the urethra near the base of the penis. The urethra then carries the sperm through the penis during ejaculation. A vasectomy interrupts sperm flow within the vas deferens. After a vasectomy, the testes still make sperm, but because the exit is blocked, the sperm die and are reabsorbed by the body.
A problem in the delicate tubes of epididymis can develop over time after vasectomy. The longer the time since the vasectomy, the greater the “back-pressure” behind the vasectomy. This “back-pressure” may cause a “blowout” in the delicate epididymal tubule, the weakest point in the system. The blowout may or may not cause symptoms, but will probably scar the epididymal tubule, thus blocking sperm flow at second point. To summarize, with time, a man with a vasectomy can develop a second obstruction deeper in the reproductive tract that can make the vasectomy more difficult to reverse. Having the skill to detect and fix this problem during vasectomy reversal is the essence of a skilled surgeon. If the surgeon simply reconnects the two freshened ends of the vas deferens without examining for a second, deeper obstruction, then the procedure can fail, as sperm would still not be able to flow out of the “corrected” system. In this case, the vas deferens must be connected to the epididymis in front of the second blockage, to bypass both blockages and allow the sperm to reenter the urethra in the ejaculate. Since the epididymal tubule is much smaller (0.3 mm diameter) than the vas deferens (3 mm diameter, 10-fold larger), epididymal surgery is far more complicated and precise than the simple vas deferens-to-vas deferens connection.
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