Vasectomy

Overview
Vasectomy is a surgical procedure in which the vasa deferentia of a male mammal are cut for the purpose of sterilization. There are some variations on the procedure such as no-scalpel (keyhole) vasectomies, in which a surgical hook, rather than a scalpel, is used to enter the scrotum.

After vasectomy, the testes remain in the scrotum where Leydig cells continue to produce testosterone and other male hormones that continue to be secreted into the bloodstream. Some studies find that sexual desire (libido) is unaffected in over 90% of vasectomized men whereas other studies find higher rates of diminished sexual desire. The sperm-filled fluid from the testes contributes about 10% to the volume of an ejaculation (in men who are not vasectomized) and does not significantly affect the appearance, texture, or taste of the ejaculate.

When the vasectomy is complete, sperm can no longer exit the body through the penis. They are broken down and absorbed by the body. Much fluid content is absorbed by membranes in the epididymis, and much solid content is broken down by macrophages and re-absorbed via the blood stream. Sperm is matured in the epididymis for about a month once it leaves the testicles. Approximately 50% of the sperm produced never make it to ejaculation in a non-vasectomized man. After vasectomy, the membranes increase in size to absorb more fluid, and more macrophages are recruited to break down and re-absorb more of the solid content. The fraction of sperms that exceed the digestive capabilities of macrophages exit into the scrotum as sperm granulomas.

Effectiveness
Early failure rates, i.e. pregnancy within a few months after vasectomy, are below 1%, but the effectiveness of the operation and rates of complications vary with the level of experience of the surgeon performing the operation and the surgical technique used.

Although late failure, i.e. pregnancy after recanalization of the vasa deferentia, is very rare, it has been documented.

Popularity
How popular vasectomy is as a birth control method varies by age and nationality. Men in their mid 30s to mid 40s are most likely to have a vasectomy.

Compared to tubal ligations
The rate of vasectomies to tubal ligations worldwide is extremely variable, and the statistics are mostly based on questionnaire studies rather than actual counts of procedures performed. In the U.S. in 2005, the CDC published state by state details of birth control usage by method and age group. Overall, tubal ligation is ahead of vasectomy but not by a large factor. In Britain vasectomy is more popular than tubal ligation, though this statistic may be as a result of the data-gathering methodology. Couples who opt for tubal ligation do so for a number of reasons, including:


 * Convenience of coupling the procedure with delivery at a hospital
 * Fear of side effects in the man
 * Fear of surgery in the man

Couples who choose vasectomy are motivated by, among other factors:


 * The lower cost of vasectomy
 * The simplicity of the surgical procedure
 * The lower mortality of vasectomy
 * Fear of surgery in the woman

Complications
Short-term complications include temporary bruising and bleeding, known as hematoma. The primary long-term complication is a permanent feeling of pain - chronic post-vasectomy Pain.

Animal and human data indicate that vasectomy does not increase atherosclerosis and that increases in circulating immune complexes after vasectomy are transient. Furthermore, the weight of the evidence regarding prostate and testicular cancer suggests that men with vasectomy are not at increased risk of these cancers.

Post-Vasectomy Pain Syndrome
Post-Vasectomy Pain Syndrome (PVPS), genital pain of varying intensity that may last for a lifetime, is estimated to appear in between 5% and 33% of vasectomized men, depending on the severity of pain that qualifies for the particular study   In one study, vasectomy reversal was found to be 69% effective for reducing the symptoms of chronic post-vasectomy pain. Treatment options for 31% of patients whose pain did not respond to vasectomy reversal were limited. The study was very small, only evaluating 13 patients, making it difficult to draw solid conclusions. In severe cases orchiectomy has been resorted to.

Possible Vasectomy-Dementia Link
Researchers reported in February 2007 that a survey of a small number of men with a rare form of dementia found that more than twice as many as would be expected had undergone vasectomies. The study has not yet been verified by other researchers, and the authors say larger studies are needed to better understand the issue.

Reversal
Although men considering vasectomies should not think of them as reversible, and most men and their spouses are satisfied with the operation, there is a procedure to reverse vasectomies using vasovasostomy (a form of microsurgery first performed by Earl Owen in 1971  ). Vasovasostomy is effective at achieving pregnancy in only 50%-70% of cases, and it is very costly, with total out-of-pocket costs in the United States ranging from $7,000 to more than $35,000. The rate of pregnancy depends on such factors as the method used for the vasectomy and the length of time that has passed since the vasectomy was performed. The reversal procedures are frequently impermanent, with occlusion of the vas recurring two or more years after the operation. Sperm counts are rarely at pre-vasectomy levels. There is evidence that men who have had a vasectomy may produce more abnormal sperm, which would explain why even a mechanically successful reversal does not always restore fertility. The higher rates of aneuploidy and diploidy in the sperms of men who have undergone vasectomy reversal may lead to a higher rate of birth defects.

In order to allow a possibility of reproduction (via artificial insemination) after vasectomy, some men opt for cryostorage of sperm before sterilization.

Various reversible male contraceptives are in research and development, but none are available. Many of these involve the implantation of micro-valves.

Availability

 * In the UK vasectomy is often available free of charge through the National Health Service upon referral by one's GP. However, some PCTs do not fund the procedure. There are private clinics (such as Marie Stopes International) who perform the operation with short waiting times.