Current Management of Vasectomy
Vasectomy, a form of male sterilization utilizing bilateral disruption of the vas deferens to halt the transmission of spermatozoa during ejaculation, is an outpatient procedure that can be performed in the office setting under local anesthesia, with most patients reporting only minimal postoperative pain. Unlike many of the other methods of contraception, which require continuous usage or repeat administrations, vasectomy needs to be performed only once for a man to be rendered durably sterile.
Despite advances in other methods of family planning during the last several decades, vasectomy has remained among the most popular forms of contraception. The safety, simplicity and durability of the procedure make it an attractive option for patients and physicians alike. However, many controversies remain regarding the appropriate management of patients after the procedure. This article discusses the importance of preoperative counseling and reviews vasectomy techniques and outcomes after sterilization.
Worldwide, it has been estimated that 5% of all married couples of reproductive age — or approximately 42 to 60 million people — depend on vasectomy as their sole contraceptive method.1,2 This number varies widely between countries, with the highest rate of vasectomy (23% of men) reported in New Zealand.3
Vasectomies are much more common in white men than in black men (14% vs. 2%).4 In the United States, 11% of women of reproductive age rely on vasectomy for family planning. Those most likely to elect vasectomy as their contraceptive method of choice include women between 30 and 45 years of age, married women, and women with at least a high school education.
Vasectomy can be performed under local anesthesia with relative ease, and the patient may return to his normal level of activity within several days of the procedure.
Given the finality of vasectomy, thorough preoperative counseling regarding the risks and benefits of the procedure and alternatives to it is imperative. In addition, reasonable expectations regarding postoperative recovery should be fostered. Patients should be forewarned about the need for continued postoperative surveillance. After counseling, the patient should be able to demonstrate a clear understanding of the time delay between surgery and achievement of azoospermia and of the need for postoperative semen analyses to confirm the absence of spermatozoa.
In addition, every patient should be able to demonstrate a clear understanding of the potential complications that may result from the procedure. Specifically, the risk of chronic inflammation and post-vasectomy pain syndrome (PVPS) should be discussed. Patients with PVPS present with intermittent or constant pain in one or both testicles after vasectomy, lasting for three or more months.
PVPS is considered relatively uncommon following vasectomy, although the incidence has been suggested to be as high as 19%. The exact mechanism of the syndrome remains unknown, but theories involving epididymal congestion, painful sperm granulomas, vascular stasis and nerve impingement have been put forth.
Most patients with PVPS can be managed conservatively with reassurance, nonsteroidal anti-inflammatory drugs, scrotal support or nerve blocks. However, patients who do not respond to these measures may need secondary surgical procedures such as vasectomy reversal, epididymectomy or spermatic cord denervation.6-9
In the past, some urologists counseled men under age 35 about a potentially increased risk of prostate cancer later in life. Although several studies published in the early 1990s reported an increased risk of prostate cancer in men having undergone vasectomy,10-12 various large-scale epidemiologic studies carried out under the auspices of the American Urological Association (AUA) have since shown no proof of a relationship between vasectomy and prostate cancer risk.13-15 Similarly, although it was suggested in the early 1980s that vasectomy may be associated with the development of atherosclerosis and cardiovascular disease, this notion has long since been dispelled.16,17
Finally, while several realistic options for the re-establishment of vasal continuity do exist, vasectomy is still considered a permanent form of male sterilization. As such, every candidate must consider his individual circumstances, both current and future, before deciding to proceed. Prior to undergoing vasectomy, every patient should be made aware of the option of “fertility insurance” by means of semen cryopreservation.
The goal of preoperative counseling should not be to dissuade or scare the patient from undergoing vasectomy. Rather, the goal should be to provide him with the knowledge necessary to make a fully informed decision. When done appropriately, preoperative counseling can result in patients who are more satisfied, more compliant and less litigious than those who receive inadequate or no counseling.
The vasectomy procedure is begun by palpation of the vas deferens through the scrotal skin. The vas is then secured with the surgeon’s fingers and the scrotal skin is opened. Access to the vas deferens may be obtained using either the conventional incisional method or the no-scalpel method popularized by Li and colleagues in the late 1980s.18 With the conventional method, a scalpel is used to make an approximately 1-cm incision either in the midline (if a single incision is used) or in each hemiscrotum (if two separate incisions are used). With the no-scalpel technique, a specialized sharp forceps is used to puncture the scrotal skin, thereby creating a hole through which the vasectomy can be performed.
After the vas deferens is identified, it is brought out through the scrotal incision and divided. A variable length of vas is resected, and the remaining free ends are occluded. To accomplish vasal occlusion, the cut ends may be secured with nonabsorbable suture, cautery, and/or metal clips. Many urologists also interpose fascia between the cut ends to minimize the risk of vasal recanalization. The crucial step for vasectomy success is vasal occlusion; the exact method of occlusion is a matter of preference.
3. Vasectomy Failures
Vasectomy is the most reliable practical method of permanent contraception. However, vasectomy failures have been reported. Most sources estimate the occurrence of undesired pregnancy following vasectomy to be approximately one in 2,000 cases.19-21 This failure rate of less than 0.1% compares favorably with the 1.85% failure rate associated with tubal ligation.22
Vasectomy failures are divided into two categories: early and late. Early failures occur within the first few months following vasectomy and are usually attributed to unprotected intercourse prior to obtaining a negative semen analysis. A vas inadvertently missed during the procedure can also cause early failure. This may occur if the surgeon excises two portions from one vas (when using a single midline incision) or if the surgeon ligates a structure other than the vas.
Late failures may occur years to decades after vasectomy and are most often attributed to recanalization of the vas deferens. The majority of vasectomy failures are early failures and occur in men who are ineffectively counseled regarding the delay between vasectomy and achievement of azoospermia.
4. Post-vasectomy Semen Analysis
While most urologists agree on the need for a semen analysis to verify the achievement of azoospermia after vasectomy, there is no consensus on the exact timing for it. Most physicians use an arbitrarily determined time period or an arbitrary number of ejaculations before obtaining a semen analysis. In a survey of 1,800 physicians performing vasectomy in the United States in 1995, Haws and associates found that post-vasectomy semen analysis was obtained at six weeks or less by 59% of the physicians, at seven to nine weeks by 29%, and at nine weeks or more by 12%.23
Rate of achievement of azoospermia
While most physicians obtain the post-vasectomy semen analysis within six weeks, a review of the available literature suggests that this may be too soon to determine whether the procedure was a success.
Figure 1, incorporating data from 12 peer-reviewed studies,24-35 shows the rate of development of post-vasectomy azoospermia plotted as a function of time. Three months after vasectomy, only 72% of men have achieved azoospermia. Six months after vasectomy, this number increases to 85%; by one year after vasectomy, 99% of men are azoospermic. This slow, constant rate suggests that the number of ejaculations after vasectomy may have only minor impact on the achievement of azoospermia.
Similarly, it has been shown that there is no association between the method of vasal occlusion or length of vas excised and the length of time required for a man to achieve azoospermia following a vasectomy.23,36-39 Given the relatively slow rate of achievement of post-vasectomy azoospermia, our current practice is to obtain a semen analysis no sooner than three months after vasectomy.
The significance of azoospermia
Post-vasectomy semen analysis may show any one of three findings:
- complete absence of spermatozoa (azoospermia),
- presence of motile spermatozoa, or
- presence of nonmotile spermatozoa.
The presence of motile spermatozoa three to six months after vasectomy indicates vasectomy failure due to technical error or to early recanalization.40 The significance of nonmotile spermatozoa detected on semen analysis depends on how long after the procedure they are found. In the early post-vasectomy period, this finding is thought to be caused by the release of nonviable residual spermatozoa in the distal reproductive tract.28 If found a significant amount of time after vasectomy, nonmotile spermatozoa generally indicate recanalization of the vas deferens.41 However, it is important to understand that the isolated finding of nonmotile spermatozoa does not necessarily signal vasectomy failure.
As shown in Table 1, 25,28,39,41,42 multiple investigators have reported on the reappearance of rare nonmotile spermatozoa years to decades after vasectomy in men previously documented to be azoospermic. It is widely believed that the presence of a small number of nonmotile spermatozoa in vasectomized men is a normal and usual result following vasectomy. Additionally, it has been shown that the risk of pregnancy from nonmotile spermatozoa is only 0.05% — which is identical to the risk of pregnancy after two azoospermic semen analyses.19,43
Although the AUA has not to date issued guidelines for the management of post-vasectomy patients, current guidelines from the British Andrology Society recommend routine centrifugation of all post-vasectomy semen specimens to increase the likelihood of detecting rare nonmotile spermatozoa.32 While semen centrifugation is a useful sperm-harvesting technique for intracytoplasmic sperm injection in men with obstructive or nonobstructive azoospermia,44 it is not currently the U.S. clinical standard of care for post-vasectomy patients. Centrifugation is an effective means of detecting rare nonmotile spermatozoa, but, as discussed earlier, the presence of rare nonmotile spermatozoa after vasectomy is of only trivial significance and should not alter patient management.
Vasectomy remains among the safest, easiest and surest methods of male sterilization. As such, it is one of the most popular methods of permanent contraception worldwide. However, despite the popularity of the technique, there has been a notable lack of consensus on the appropriate management of patients after vasectomy. We recommend waiting at least three months after vasectomy to assess azoospermia by semen analysis. A semen analysis indicating the complete absence of spermatozoa or the presence of only rare nonmotile spermatozoa is considered a marker of vasectomy success. Routine centrifugation of azoospermic semen to detect rare nonmotile spermatozoa is not currently considered the clinical standard of care in the United States.
It is clear that multiple issues must be addressed after vasectomy. In a patient’s mind, the judicious handling of these issues can make the difference between a successful sterilization and an unpleasant experience. When vasectomy is no longer represented to patients as a procedure but rather as a process, they may be more appropriately counseled on the facts — that continued follow-up after vasectomy is essential, sterility after vasectomy cannot be guaranteed, and the possibilities of spontaneous recanalization or PVPS, although small, do exist.
6. Urologic Summary
Due to its simplicity, safety and effectiveness, vasectomy has remained among the most popular forms of contraception. The failure rate is typically less than 0.1%, comparing favorably with the 1.85% failure rate for tubal ligation.
Thorough preoperative counseling regarding the risks, benefits, alternatives and permanency of vasectomy is imperative.
Reasonable expectations should be fostered in patients regarding postoperative recovery, and patients should be informed of the time delay between treatment and achievement of azoospermia and the need for postoperative semen analyses to confirm azoospermia.
Obtaining the post-vasectomy semen analysis within six weeks may be too soon to confirm success of treatment. At three months follow-up, only 72% of men have achieved azoospermia.
The majority of vasectomy failures are early failures in men who are ineffectively counseled regarding the delay between vasectomy and azoospermia.
Late vasectomy failures or the presence of motile spermatozoa may indicate recanalization of the vas deferens.