Vasectomy is a simple operation designed to make a man sterile, or unable to father a child. It is used as a means of contraception in many parts of the world. A total of about 50 million men have had a vasectomy--a number that corresponds to roughly 5 percent of all married couples of reproductive age. In comparison, about 15 percent of couples rely on female sterilization for birth control.
Approximately half a million vasectomies are performed in the United States each year. About one out of six men over age 35 has been vasectomized, the prevalence increasing along with education and income. Among married couples in this country, only female sterilization and oral contraception are relied upon more often for family planning.
Vasectomy involves blocking the tubes through which sperm pass into the semen. Sperm are produced in a man's testis and stored in an adjacent structure known as the epididymis. During sexual climax, the sperm move from the epididymis through a tube called the vas deferens and mix with other components of semen to form the ejaculate. All vasectomy techniques involve cutting or otherwise blocking both the left and right vas deferens, so the man's ejaculate will no longer contain sperm, and he will not be able to make a woman pregnant.
In the conventional approach, a physician makes one or two small incisions, or cuts, in the skin of the scrotum, which has been numbed with a local anesthetic. The vas is cut, and a small piece may be removed. Next, the doctor ties the cut ends and sews up the scrotal incision. The entire procedure is then repeated on the other side.
An improved method, devised by a Chinese surgeon, has been widely used in China since 1974. This so-called non-surgical or no-scalpel vasectomy was introduced into the United States in 1988, and many doctors are now using the technique here.
In a no-scalpel vasectomy, the doctor feels for the vas under the skin of the scrotum and holds it in place with a small clamp. Then a special instrument is used to make a tiny puncture in the skin and stretch the opening so the vas can be cut and tied. This approach produces very little bleeding, and no stitches are needed to close the punctures, which heal quickly by themselves. The newer method also produces less pain and fewer complications than conventional vasectomy.
Regardless of how it is performed, vasectomy offers many advantages as a method of birth control. Like female sterilization, it is a highly effective one-time procedure that provides permanent contraception. But vasectomy is medically much simpler than female sterilization, has a lower incidence of complications, and is much less expensive.
After vasectomy, the patient will probably feel sore for a few days, and he should rest for at least 1 day. However, he can expect to recover completely in less than a week. Many men have the procedure on a Friday and return to work on Monday. Although complications such as swelling, bruising, inflammation, and infection may occur, they are relatively uncommon and almost never serious. Nevertheless, men who develop these symptoms at any time should inform their physician.
A man can resume sexual activity within a few days after vasectomy, but precautions should be taken against pregnancy until a test shows that his semen is free of sperm. Generally, this test is performed after the patient has had 10-20 post-vasectomy ejaculations. If sperm are still present in the semen, the patient is told to return later for a repeat test.
A major study of vasectomy side effects occurring within 8 to 10 years after the procedure was published in the British Medical Journal in 1992. This study--the Health Status of American Men, or HSAM--was sponsored by the National Institute of Child Health and Human Development (NICHD). Investigators questioned 10,590 vasectomized men, and an equal number of nonvasectomized men, to see if they had developed any of 99 different disorders. After a total of 182,000 person-years of follow-up, only one condition, epididymitis/orchitis (defined as painful, swollen, and tender epididymis or testis)--was found to be more common after vasectomy. This local inflammation most often occurs during the first year after surgery. Treated with heat, it usually clears up within a week.
Disadvantages of Vasectomy
The chief advantage of vasectomy--its permanence--is also its chief disadvantage. The procedure itself is simple, but reversing it is difficult, expensive, and often unsuccessful. Researchers are studying new methods of blocking the vas that may produce less tissue damage and scarring and might thus permit more successful reversal. But these methods are all experimental, and their effectiveness has not yet been confirmed. It is possible to store semen in a sperm bank to preserve the possibility of producing a pregnancy at some future date. However, doing this is costly, and the sperm in stored semen do not always remain viable (able to cause pregnancy). For all of these reasons, doctors advise that vasectomy be undertaken only by men who are prepared to accept the fact that they will no longer be able to father a child. The decision should be considered along with other contraceptive options and discussed with a professional counselor. Men who are married or in a serious relationship should also discuss the issue with their partners. Although it is extremely effective for preventing pregnancy, vasectomy does not offer protection against AIDS or other sexually transmitted diseases. Consequently, it is important that vasectomized men continue to use condoms, preferably latex, which offer considerable protection against the spread of disease, in any sexual encounter that carries the risk of contracting or transmitting infection.
Masculinity and Sexuality
Vasectomy does not affect production or release of testosterone, the male hormone responsible for a man's sex drive, beard, deep voice, and other masculine traits. The operation also has no effect on sexuality. Erections, climaxes, and the amount of ejaculate remain the same.
Occasionally, a man may experience sexual difficulties after vasectomy, but these almost always have an emotional basis and can usually be alleviated with counseling. More often, men who have undergone the procedure, and their partners, find that sex is more spontaneous and enjoyable once they are freed from concerns about contraception and accidental pregnancy.
Immune Reactions to Sperm
After vasectomy, the testes continue to make sperm. When the sperm cells die, they are absorbed by the body, much like unused sperm in a nonvasectomized man. Nevertheless, many vasectomized men develop immune reactions to sperm, although current evidence indicates that these reactions do not cause any harm.
Ordinarily, sperm do not come in contact with immune cells, so they do not elicit an immune response. But vasectomy breaches the barriers that separate immune cells from sperm, and many men develop anti-sperm antibodies after undergoing the procedure. This has given rise to concern on the part of doctors and researchers, because immune reactions against parts of one's own body sometimes cause disease. Rheumatoid arthritis, juvenile diabetes, and multiple sclerosis are just some of the illnesses suspected or known to be caused by immune reactions of this type.
Immune reactions can also contribute to the development of atherosclerosis, the clogging of arteries that leads to heart attacks. In the late 1970s, after a study of 10 monkeys showed an increased risk of atherosclerosis in vasectomized animals, doctors became concerned that vasectomy might increase the risk of heart disease in men.
Other, more persuasive research results, however, indicated that these concerns were not warranted. In particular, the HSAM study provided a high level of reassurance. Researchers conducting this study found no evidence that vasectomized men were more likely than others to develop heart disease or any other immune illnesses.
But just as concerns about heart disease and immune ailments following vasectomy were being laid to rest, worries about prostate cancer were taking their place.
Although the HSAM and a number of other studies showed no increase in cancer among vasectomized men, three separate hospital-based studies published in 1990 reported positive correlations between vasectomy and prostate cancer. However, a well-regarded 1991 study found no such relationship.
Because of the importance of the issue, all of this research has been carefully analyzed, and scientists have identified several potential problems in the studies. It is possible, for example, that men who choose vasectomy for contraception have above average access to health care. In particular, these men may be more likely than others to visit urologists--physicians whose specialty includes the male reproductive organs, and they might thus be more likely to receive an accurate diagnosis of prostate cancer, a disease that often causes no symptoms and remains undiagnosed. If this were the case, vasectomy might falsely appear to increase the risk of this cancer.
In October 1991, the World Health Organization (WHO) sponsored a meeting of experts from around the world to evaluate the available evidence regarding a link between vasectomy and prostate cancer. Because additional concerns had been raised about a possible association between vasectomy and testicular cancer, evidence for such an association was also weighed at the meeting. The assembled experts concluded that a causal relationship between vasectomy and cancer of either the prostate or testis was unlikely. This conclusion was based in large measure on an overview of study results. But it was strengthened by the absence of a biological explanation of how vasectomy might product any form of cancer.
Following the WHO meeting, two additional studies of vasectomized men found no increased risk of either prostate cancer or all cancers combined. Subsequently, a study conducted in three regions of the United States suggested that the subgroup of men who had a vasectomy before age 35 might have a slightly increased risk of developing prostate cancer. However, the size of this subgroup was not large enough to make the result conclusive. The study did not find any increased cancer risk in men who underwent vasectomy after age 35.
In 1993, a noted team of Harvard epidemiologists published findings from two large studies in the Journal of the American Medical Association (JAMA). One of these studies was retrospective (backward-looking), while the other was prospective and followed new patients. Both found vasectomy to be associated with a moderately elevated relative risk of prostate cancer that increased with time after the procedure. After more than 20 years, a vasectomized man appeared to be twice as likely to develop prostate cancer as a nonvasectomized man of the same age. Although this conclusion may seem startling, scientists generally consider risk findings of this magnitude to be of doubtful significance.
The studies were examined by experts in several professional organizations as well as in a JAMA article. The authors of this article concluded that the studies could neither be relied upon nor ignored and that further research was essential.
These authors pointed out that, since the causes of prostate cancer remain unknown, it had been impossible to assure that risk factors for the illness were equally distributed between the vasectomized and nonvasectomized men. In one of the studies, the men who had undergone vasectomy had a lower overall death rate than the men who had not, supporting the likelihood that the two groups had different characteristics. Differences of this type might have affected prostate cancer risk, producing study results that misleadingly implicated vasectomy as a cause of prostate cancer.
Like others before them, these scientists also noted the lack of evidence for any biological mechanism that could link vasectomy with prostate cancer.
In 1993, NICHD convened a meeting at which an expert panel considered published data, preliminary results from studies in progress, and an analysis of eight epidemiologic studies, including the two reports mentioned above. The panelists concluded that the positive associations between vasectomy and prostate cancer found in some studies might or might not be valid. Scientists agree, however, that if any increased risk is caused by vasectomy, it is relatively small.
WHO is currently conducting a major study of vasectomy and prostate cancer in several developing countries, and three other studies are ongoing in the United States and Canada. Scientists expect these investigations to help resolve the issue.
In the interim, most physicians will be guided by NICHD's expert panel of 1993 which concluded there is insufficient basis for recommending any change in current clinical or public health practice. Providers should continue to offer vasectomy and to perform the procedure, the panel said. Vasectomy reversal is not warranted to prevent prostate cancer, and screening for prostate cancer should not be any different for men who have had a vasectomy than for those who have not undergone the procedure.
Vasectomy has been used for about a century as a means of sterilization. It has a long track record as a safe and effective method of contraception and is relied upon by millions of people throughout the world. On the basis of much evidence, experts believe that vasectomy can safely continue to be used as it has been in the past, while further research is carried out.
Source: National Institutes of Health
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