American Urological Association - Vasectomy

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Home Guidelines Clinical Guidelines Vasectomy (2012; Amended 2015)

Vasectomy

Published 2012; Amended 2015

Unabridged version of this Guideline [pdf]

Panel Members

Ira D. Sharlip, Arnold M. Belker, Stanton Honig, Michel Labrecque, Joel L. Marmar, Lawrence S. Ross, Jay I. Sandlow, David C. Sokal

Executive Summary

Note to the Reader:

Please note that this Guideline was edited in 2015 to include additional information related to vasectomy and the risk of prostate cancer.

Purpose

The purpose of this Guideline is to provide guidance to clinicians who offer vasectomy services. This guidance covers pre-operative evaluation and consultation of prospective vasectomy patients; techniques for local anesthesia, isolation of the vas deferens and occlusion of the vas deferens during vasectomy; post-operative follow-up; post-vasectomy semen analysis (PVSA) and potential complications and consequences of vasectomy.

Methods

A systematic review of the literature using the MEDLINE and POPLINE databases (search dates January 1949 to August 2011) was conducted to identify peer-reviewed publications relevant to vasectomy. The search identified almost 2,000 titles and abstracts. Almost 900 articles were retrieved for full-text review. These yielded an evidence base of 275 articles after application of inclusion and exclusion criteria. These publications were used to create the evidence-based portion of the Guideline. When sufficient evidence existed, the body of evidence for a particular treatment was assigned a strength rating of A (high), B (moderate) or C (low). Additional information is provided as Clinical Principles and Expert Opinion when insufficient evidence existed.

Guideline Statements

1. A preoperative interactive consultation should be conducted, preferably in person. If an in-person consultation is not possible, then preoperative consultation by telephone or electronic communication is an acceptable alternative. Expert Opinion

2. The minimum and necessary concepts that should be discussed in a preoperative vasectomy consultation include the following: Expert Opinion

  • Vasectomy is intended to be a permanent form of contraception.
  • Vasectomy does not produce immediate sterility.
  • Following vasectomy, another form of contraception is required until vas occlusion is confirmed by post- vasectomy semen analysis (PVSA).
  • Even after vas occlusion is confirmed, vasectomy is not 100% reliable in preventing pregnancy.
  • The risk of pregnancy after vasectomy is approximately 1 in 2,000 for men who have post-vasectomy azoospermia or PVSA showing rare non-motile sperm (RNMS).
  • Repeat vasectomy is necessary in ≤1% of vasectomies, provided that a technique for vas occlusion known to have a low occlusive failure rate has been used.
  • Patients should refrain from ejaculation for approximately one week after vasectomy.
  • Options for fertility after vasectomy include vasectomy reversal and sperm retrieval with in vitro fertilization. These options are not always successful, and they may be expensive.
  • The rates of surgical complications such as symptomatic hematoma and infection are 1-2%. These rates vary with the surgeon's experience and the criteria used to diagnose these conditions.
  • Chronic scrotal pain associated with negative impact on quality of life occurs after vasectomy in about 1-2% of men. Few of these men require additional surgery.
  • Other permanent and non-permanent alternatives to vasectomy are available.

3. Clinicians do not need to routinely discuss prostate cancer, coronary heart disease, stroke, hypertension, dementia or testicular cancer in pre-vasectomy counseling of patients because vasectomy is not a risk factor for these conditions. Standard (Evidence Strength Grade B)

4. Prophylactic antimicrobials are not indicated for routine vasectomy unless the patient presents a high risk of infection. Recommendation (Evidence Strength Grade C)

5. Vasectomy should be performed with local anesthesia with or without oral sedation. If the patient declines local anesthesia or if the surgeon believes that local anesthesia with or without oral sedation will not be adequate for a particular patient, then vasectomy may be performed with intravenous sedation or general anesthesia. Expert Opinion

6. Isolation of the vas should be performed using a minimally-invasive vasectomy (MIV) technique such as the no-scalpel vasectomy (NSV) technique or other MIV technique. Standard (Evidence Strength Grade B)

7. The ends of the vas should be occluded by one of three divisional methods:

  1. Mucosal cautery (MC) with fascial interposition (FI) and without ligatures or clips applied on the vas;
  2. MC without FI and without ligatures or clips applied on the vas;
  3. Open ended vasectomy leaving the testicular end of the vas unoccluded, using MC on the abdominal end and FI;

    OR by the non-divisional method of extended electrocautery. Recommendation (Evidence Strength Grade C)

8. The divided vas may be occluded by ligatures or clips applied to the ends of the vas, with or without FI and with or without excision of a short segment of the vas, by surgeons whose personal training and/or experience enable them to consistently obtain satisfactory results with such methods. Option  (Evidence Strength Grade C)

9. Routine histologic examination of the excised vas segments is not required. Expert Opinion

10. Men or their partners should use other contraceptive methods until vasectomy success is confirmed by PVSA. Clinical Principle

11. To evaluate sperm motility, a fresh, uncentrifuged semen sample should be examined within two hours after ejaculation.  Expert Opinion

12. Patients may stop using other methods of contraception when examination of one well-mixed, uncentrifuged, fresh post-vasectomy semen specimen shows azoospermia or only rare non-motile sperm (RNMS or ≤ 100,000 non-motile sperm/mL). Recommendation (Evidence Strength Grade C)

13. Eight to sixteen weeks after vasectomy is the appropriate time range for the first PVSA. The choice of time to do the first PVSA should be left to the judgment of the surgeon. Option (Evidence Strength Grade C)

14. Vasectomy should be considered a failure if any motile sperm are seen on PVSA at six months after vasectomy, in which case repeat vasectomy should be considered. Expert Opinion

15. If > 100,000 non-motile sperm/mL persist beyond six months after vasectomy, then trends of serial PVSAs and clinical judgment should be used to decide whether the vasectomy is a failure and whether repeat vasectomy should be considered. Expert Opinion

Purpose

The purpose of this Guideline is to provide guidance to clinicians who offer vasectomy services. The Guideline covers pre-vasectomy evaluation and consultation of prospective vasectomy patients; techniques for local anesthesia, isolation of the vas deferens and occlusion of the vas deferens during vasectomy; post-operative follow-up; post-vasectomy semen analysis (PVSA) to verify sterility and potential complications and consequences of vasectomy. Currently, the practice of vasectomy is characterized by wide variation in pre-operative counseling, surgical technique and post-operative follow-up. The intent of this Guideline is to provide a set of approaches and procedures that maximizes successful vasectomy outcomes and minimizes failure and other adverse events.

The strategies and approaches recommended in this document were derived from evidence-based and consensus-based processes. There is a continually expanding literature on vasectomy. The Panel  notes that this document constitutes a clinical approach to the practice of vasectomy. This Guideline is not intended to replace the judgment of an individual clinician faced with a particular patient. As the science relevant to vasectomy evolves and improves, the strategies presented here will require updating to remain consistent with the highest standards of clinical care.

Methodology

Process for Literature Selection. A systematic review was conducted to identify published articles relevant to key questions specified by the Panel (See Appendix C). The key questions focused on identifying necessary elements of pre-operative evaluation and consultation, optimal procedures for anesthetic administration, the least traumatic and most effective procedures for isolation of the vas deferens, the most effective procedures for occluding the vas deferens, the complications and consequences of vasectomy and the necessary components of post-operative follow-up, including semen analysis to verify sterility.

Literature searches were performed using the MEDLINE® and POPLINE® databases from January 1949 to August 2011 with the goal of identifying literature broadly relevant to the practice of vasectomy. This literature included studies that focused on the prevalence of vasectomy; the demographics of patients and couples who chose vasectomy; vasectomy operative techniques, including techniques for vas isolation and vas occlusion and associated failure rates; short-term and long-term complications of vasectomy, other outcomes potentially associated with vasectomy (e.g., coronary heart disease, stroke, prostate and testicular cancer, sexual outcomes, psychosocial outcomes) and PVSA procedures and timing. Inclusion criteria for operative procedures were conventional vasectomy (CV) and minimally-invasive vasectomy (MIV), including the no-scalpel vasectomy (NSV) technique. All methods for occluding the vas were included. The following topics were excluded from the scope of the review: laparoscopic vasectomy, vasectomy reversal, post-vasectomy options for pregnancy, treatment of post-vasectomy pain syndrome, examination of antibodies to antigens other than sperm post-vasectomy and techniques for teaching vasectomy. Articles on antibiotic prophylaxis also were excluded as the topic of antibiotic prophylaxis in surgical procedures without entering the urinary tract is covered in an AUA Best Practice Policy [pdf]. All settings and all ages of vasectomy patients were included. All study designs were included except for single-group cohort studies on immediate post-operative complications with fewer than 500 participants. Review article references were checked to ensure inclusion of all possibly relevant studies. Multiple reports on the same patient group were carefully examined to ensure exclusion of redundant information.

Nearly 2,000 citations were reviewed by title and/or abstract. After application of inclusion and exclusion criteria, 275 articles were chosen to form the evidence base of this Guideline. Data were extracted on study design (e.g., randomized controlled trial, comparative observational study, case-series); pre-operative, operative and post-operative parameters; complications and other consequences of vasectomy (e.g., patient satisfaction, patient regret) and vasectomy effectiveness and failure rates.

Quality of Individual Studies and Determination of Evidence Strength. Quality of individual studies that were randomized controlled trials (RCTs) or comparative observational studies was assessed using the Cochrane Risk of Bias tool.1 Since there is no widely-accepted quality assessment tool for single-cohort observational studies, the quality of these studies was not assessed.

The categorization of evidence strength is conceptually distinct from the quality of individual studies. Evidence strength refers to the body of evidence available for a particular question and includes consideration of study design; individual study quality; the consistency of findings across studies; the adequacy of sample sizes and the generalizability of samples, settings and treatments for the purposes of the Guideline. The AUA categorizes body of evidence strength (ES) as Grade A (well-conducted RCTs or exceptionally strong observational studies), Grade B (RCTs with some weaknesses of procedure or generalizability or generally strong observational studies) or Grade C (observational studies that are inconsistent, have small sample sizes, or have other problems that potentially confound interpretation of data).

AUA Nomenclature: Linking Statement Type to Evidence Strength. The AUA nomenclature system explicitly links statement type to body of evidence strength and the Panel's judgment regarding the balance between benefits and risks/burdens (see Table 2).2 Standards are directive statements that an action should (benefits outweigh risks/burdens) or should not (risks/burdens outweigh benefits) be undertaken based on Grade A or Grade B evidence. Recommendations are directive statements that an action should (benefits outweigh risks/burdens) or should not (risks/burdens outweigh benefits) be undertaken based on Grade C evidence. Options are non-directive statements that leave the decision to take an action up to the individual clinician and patient because the balance between benefits and risks/burdens appears relatively equal or appears unclear; Options may be supported by Grade A, B or C evidence. For some clinical issues, there was little or no evidence from which to construct evidence-based statements. Where gaps in the evidence existed, the Panel provides guidance in the form of Clinical Principles or Expert Opinion with consensus achieved using a modified Delphi technique if differences of opinion existed among Panel members.3 A Clinical Principle is a statement about a component of clinical care that is widely agreed upon by urologists or other clinicians for which there may or may not be evidence in the medical literature. Expert Opinion refers to a statement, achieved by consensus of the Panel, that is based on members' clinical training, experience, knowledge and judgment and for which there is no evidence.

Panel Selection and Peer Review Process. The Vasectomy Panel was created in 2008 by the American Urological Association Education and Research, Inc. (AUA). The Practice Guidelines Committee (PGC) of the AUA selected the Panel Chair and Vice Chair who in turn appointed the additional panel members, all of whom have specific expertise with regard to vasectomy.

The AUA conducted an extensive peer review process. The initial draft of this Guideline was distributed to 72 peer reviewers; 55 responded with comments. The panel reviewed and discussed all submitted comments and revised the draft as needed. Since the changes were substantial, a second draft was circulated to 64 peer reviewers. The panel reviewed and discussed all submitted comments in response to this second round of peer review and again revised the document. Once finalized, the Guideline was submitted for approval to the PGC. It was then submitted to the AUA Board of Directors for final approval.  Funding of the panel was provided by the AUA. Panel members received no remuneration for their work.

Table 2: AUA Nomenclature
Linking Statement Type to Evidence Strength

Standard: Directive statement that an action should (benefits outweigh risks/burdens) or should not (risks/burdens outweigh benefits) be taken based on Grade A or B evidence

Recommendation: Directive statement that an action should (benefits outweigh risks/burdens) or should not (risks/burdens outweigh benefits) be taken based on Grade C evidence

Option: Non-directive statement that leaves the decision regarding an action up to the individual clinician and patient because the balance between benefits and risks/burdens appears equal or appears uncertain based on Grade A, B or C evidence

Clinical Principle:  a statement about a component of clinical care that is widely agreed upon by urologists or other clinicians for which there may or may not be evidence in the medical literature

Expert Opinion: a statement, achieved by consensus of the Panel, that is based on members' clinical training, experience, knowledge, and judgment for which there is no evidence

The Practice of Vasectomy

The Importance of Vasectomy

Vasectomy is the most common non-diagnostic operation performed by urologists in the United States (US). Estimates of the number of vasectomies performed annually in the US vary depending on survey type. Data from the National Study of Family Growth in which only married couples were polled indicate a range from 175,000 to 354,000.4 In a physician survey, an estimated 526,501 vasectomies were performed in the US in 2002.5 This number seems to have been approximately stable for the previous decade. More than 75% of vasectomies in the US are done by urologists, and about 90% of urology practices in the US perform vasectomy.5-6

In 2002, data collected in the US show that vasectomy was used by 5.7% of men ages 15-44 and that this represents the fourth most commonly-used contraceptive method. The first three were condoms, used by 29.5% of men, oral contraceptives for women used by 25.6% of couples and tubal ligation used by 8.1% of couples.7 Compared to tubal ligation , which is also a method of permanent contraception, vasectomy is equally effective in preventing pregnancy; however, vasectomy is simpler, faster, safer and less expensive. Vasectomy is one of the most cost-effective of all methods of contraception; its cost is about one-fourth of the cost of tuba lligation.8 Vasectomy requires less time off work, requires only local rather than general anesthesia and is usually performed in a doctor's office or clinic. The potential complications of vasectomy are less serious than those of tubal ligation.

Despite the clear advantages of vasectomy, prevalence data for 1998-2002 show that tubal ligation was performed about two to three times more often than vasectomy.4 Among all women in 2002, married and unmarried, ages 15 to 44 years in the United States, only 5.7% relied on vasectomy for contraception compared to 16.7% who relied on tubal ligation.9 Even among married women and married men who desire permanent contraception, in the US the prevalence of tubal ligation has exceeded the prevalence of vasectomy.10

Worldwide, the discrepancy between vasectomy and tubal ligation is even more marked than in the US. Data compiled in 2008 by the Population Division of the Department of Economic and Social Affairs of the United Nations show that 33 million married women ages 15-49 relied on vasectomy for contraception compared to 225 million who relied on tubal ligation.11 There are only eight nations in which vasectomy use is equal to or more frequent than tubal ligation for contraception – Korea, Canada, the United Kingdom, New Zealand, Bhutan, the Netherlands, Denmark and Austria (World Contraceptive Use 2011).

Given that vasectomy and tubal ligation  have equivalent contraceptive effectiveness and that vasectomy enjoys advantages compared to tubal sterilization of lower cost, less pain, greater safety and faster recovery, vasectomy should be considered for permanent contraception much more frequently than is the current practice in the United States and most nations of the world.

Preoperative Practice

Background Information About Who Chooses Vasectomy and Why

Reasons for Choosing Vasectomy. Several studies have addressed the reasons that men or their partners choose vasectomy.10,12-16 The decision for a partner to undergo a sterilization procedure usually is initiated by the female partner. The decision about which partner undergoes a sterilization procedure often is based on information obtained by one of the partners from medical professionals or from friends. Dissatisfaction with or failure of other contraceptive methods may prompt one or both partners to consider surgical sterilization for one of them. In the US, couples with higher numbers of children, higher educational levels and Caucasian ethnicity are more likely to choose vasectomy. 10

One study surveyed 400 couples regarding their choice of sterilization. Vasectomy was chosen when it was believed to be "easier" than tubal ligation, the physician recommended a vasectomy, there was effective couple communication and the previous method of contraception involved the use of condoms. The use of an intrauterine device (IUD) and the use of coitus interruptus were associated with the selection of tubal ligation. More people known by the wife to be satisfied with either vasectomy or tubal ligation predicted the choice of either vasectomy or tubal occlusion.12

An additional study looked at 84 couples in Scotland who selected vasectomy for contraception. In 46% of couples, both spouses were willing to be sterilized, whereas 23% of men requested vasectomy because their wives were unwilling to be sterilized and 24% of men insisted on vasectomy as their contribution to the partnership. The remaining couples gave medical reasons contraindicating a tubal ligation. The main influences for making the choice of vasectomy were favorable reports from other men (40%) and recommendations by general practitioners (21%).13

One group examined the psychological correlates of vasectomy in 74 men seeking vasectomy at a urology clinic in a tertiary care teaching hospital in the mid-western US. Half of the men had contemplated vasectomy for one year or less and 85% had a high level of certainty regarding their decision. Ninety-one percent of men indicated that their wives or partners were involved in the decision and 90% indicated that their wives or partners were very certain about the decision (data were not collected from the partners). Mean anxiety level was 3.5 out of 10 (10 was the highest possible anxiety level). The most common reasons for anxiety were anticipated pain (27%) and fear of the unknown (23%). Finality of the procedure was a source of anxiety in only 5%. Fifteen percent of men indicated they understood that vasectomy was not reversible, while 30% believed that it was reversible.14

One group reported on 719 men undergoing vasectomy compared to similar men identified from a national practice-based survey. The most common reason for choosing vasectomy over other dependably reversible methods of contraception was that vasectomy was perceived as the most secure way of avoiding pregnancy (50% of respondents). Twenty-two percent of respondents stated that the main reason was that they or their partners disliked other contraceptive measures, and 7% reported the reason was a recent unplanned pregnancy or pregnancy scare. Sixty-two percent of men responded that they chose male sterilization over tubal ligation because it was safer and simpler; an additional 14% stated it was their turn to take responsibility for contraception. Health care providers (31%) were the most commonly reported source of information that helped in the decision-making process, followed by wives/partners (25%) and friends (23%).15

Characteristics of Patients and Couples Who Chose Vasectomy. Several studies examined the characteristics of men or their partners who choose vasectomy.14,15,17-19 One such study examined data from the 1991 National Survey of Men and focused on a subset of 1,671 married men aged 20 to 39 years. Eleven and a half percent of men previously had a vasectomy and 12.6% of women had undergone a tubal ligation. Characteristics that were significantly (p<0.05) associated with choosing a vasectomy were older husband's age, white race of either spouse, living in the western US, smaller number of pregnancies in the current marriage, longer duration of marriage, prior failure with a male method of contraception and wife without religious affiliation. The husband's religion had no effect on the choice of vasectomy.17

In a large case control study on the relationship of vasectomy and prostate cancer from New Zealand, the demographic characteristics of 1,261 men or their partners who chose a vasectomy were examined.18 Significant predictors for vasectomy included advanced vocational qualifications, non-Catholic men and men who had fathered one to five children compared with men who had no children. Men with greater numbers of marriages and with more highly-educated wives were significantly more likely to have had a vasectomy (p<0.05). After adjusting for age, the following characteristics were not significant predictors (p>0.05) for vasectomy: socioeconomic status, geographic region of residence and age at first marriage.18

Additional reporting included characteristics of men undergoing vasectomy compared to a comparison group. Men undergoing vasectomy differed from the comparison group as follows: a higher percentage were married or cohabitating (91% vs 62% in the general US population), a higher proportion of non-Hispanic whites (87% vs 75%) and a greater percentage of vasectomized men had a bachelor's degree (48% vs 25%). The response rate for this survey was low: only 21% of eligible practices provided data.15

One study examined the use of vasectomy in the 2002 National Survey of Family Growth, a nationally representative survey of US residents ages 15-44 years. They evaluated differences between groups of patients in which the man did and did not have a vasectomy. For men between 30-45 years of age, white race, ever being married, older age, and increasing number of offspring were associated with increased utilization of vasectomy.16

An additional study also examined data from male participants in the 2002 National Survey of Family Growth. They found that 13.3% of married men reported having had a vasectomy and 13.8% reported tubal sterilization in their partners. It is notable that tubal sterilization was reported by 21.3% of married women participants of the same ages in the 2002 National Survey of Family Growth. The likelihood of vasectomy increased with older age and greater number of biological children, non-Hispanic white ethnicity and having ever gone to a family planning clinic. Tubal ligation as the contraceptive method was more likely among partners of men who had not attended college, those of older age and those with live births.10

General Guideline Statements

Guideline Statement 1

A preoperative interactive consultation should be conducted, preferably in person. If an in-person consultation is not possible, then preoperative consultation by telephone or electronic communication is an acceptable alternative. Expert Opinion

Discussion


Guideline Statement 2

The minimum and necessary concepts that should be discussed in a preoperative vasectomy consultation include the following: Expert Opinion

  • Vasectomy is intended to be a permanent form of contraception.
  • Vasectomy does not produce immediate sterility.
  • Following vasectomy, another form of contraception is required until vas occlusion is confirmed by post- vasectomy semen analysis (PVSA).
  • Even after vas occlusion is confirmed, vasectomy is not 100% reliable in preventing pregnancy.
  • The risk of pregnancy after vasectomy is approximately 1 in 2,000 for men who have post-vasectomy azoospermia or PVSA showing rare non-motile sperm (RNMS).
  • Repeat vasectomy is necessary in ≤1% of vasectomies, provided that a technique for vas occlusion known to have a low occlusive failure rate has been used.
  • Patients should refrain from ejaculation for approximately one week after vasectomy.
  • Options for fertility after vasectomy include vasectomy reversal and sperm retrieval with in vitro fertilization. These options are not always successful, and they may be expensive.
  • The rates of surgical complications such as symptomatic hematoma and infection are 1-2%. These rates vary with the surgeon's experience and the criteria used to diagnose these conditions.
  • Chronic scrotal pain associated with negative impact on quality of life occurs after vasectomy in about 1-2% of men. Few of these men require additional surgery.
  • Other permanent and non-permanent alternatives to vasectomy are available.

Discussion


Guideline Statement 3

Clinicians do not need to routinely discuss prostate cancer, coronary heart disease, stroke, hypertension, dementia or testicular cancer in pre-vasectomy counseling of patients because vasectomy is not a risk factor for these conditions. Standard

Discussion


Guideline Statement 4

Prophylactic antimicrobials are not indicated for routine vasectomy unless the patient presents a high risk of infection. Recommendation

Discussion


Techniques for Local Anesthesia

Guideline Statement 5

Vasectomy should be performed with local anesthesia with or without oral sedation. If the patient declines local anesthesia or if the surgeon believes that local anesthesia with or without oral sedation will not be adequate for a particular patient, then vasectomy may be performed with intravenous sedation or general anesthesia. Expert Opinion

Discussion


Vas Isolation

Background Information About Vas Isolation

Vas Isolation Techniques.  There are two key surgical steps in performing vasectomy: 1) isolation of the vas and 2) occlusion of the vas. The risks of intraoperative and early postoperative pain, bleeding and infection are related mainly to the method of vas isolation. The success and failure rates of vasectomy are related to the method of vas occlusion (see next section titled Vas Occlusion Techniques).  Methods of vas isolation include Conventional Vasectomy (CV) and Minimally-Invasive Vasectomy (MIV), which includes no-scalpel vasectomy (NSV). For definitions, see Table 3 above.

Conventional Vasectomy (CV). CV technique was the most common technique before the introduction of MIV techniques and special vasectomy instruments. CV is performed by making either one midline incision or bilateral scrotal incisions using a scalpel. Incisions are usually from 1.5 - 3 cm. No special instruments are used during CV, and the vas usually is grasped with a towel clip or an Allis forceps. During CV, the area of scrotal dissection usually is much larger than occurs with MIV techniques.

No-Scalpel Vasectomy (NSV). The no-scalpel vasectomy technique was developed in 1974 in China by Dr. Li Shunqiang to make vasectomy a more acceptable method of contraception. The NSV isolation technique was the first minimally-invasive technique for vasectomy and is described in detail in text and with diagrams by Li et al. (1991).222 An excellent description of NSV technique also can be found in training materials prepared by EngenderHealth223. Note that the NSV technique is a method of vas isolation and does not specify a method of vas occlusion. For a detailed description of the NSV technique, see Appendix A.

Strictly speaking, to be called a Li no-scalpel vas isolation technique, all of the following surgical steps must be observed:

  1. Use vas ring clamp and vas dissector, both of which have been specially designed for no-scalpel vasectomy
  2. Apply the vas ring clamp around the vas, perivasal tissue and overlying skin before making the skin opening
  3. Create a skin opening of ≤10 mm by piercing the skin with the vas dissector followed by spreading the tissue overlying the vas with the vas dissector to expose the bare anterior wall of the vas
  4. Pierce the bare vas with one tip of the vas dissector
  5. Then use a supination maneuver to elevate the vas above the skin opening
  6. Re-grasp a partial thickness of the vas with the vas ring clamp rather than encircling the vas with the ring clamp
  7. Complete the posterior dissection with the vas dissector to isolate the vas from surrounding perivasal tissue and vessels
  8. Divide the vas, with or without excision of a vas segment, and then occlude the vas with the surgeon's preferred technique for vas occlusion
  9. Leave the skin opening unsutured except in rare cases that may require a skin suture

If all of these specific steps are not used, then the vasectomy should be called a minimally-invasive vasectomy (MIV) rather than a no-scalpel vas isolation technique. As an example, if the only difference is creation of a skin opening ≤10 mm with a scalpel before applying the vas ring clamp around the vas, the technique is labeled as an MIV technique because each exact step of the NSV technique was not used.211

When difficulty in isolating the vas is encountered or anticipated, as may be expected with a history of surgery for testicular maldescent or perivasal scarring from a previous operative procedure, a larger incision similar to the incision typically used for CV may be needed. Even in these more difficult vasectomies, the vas ring clamp and vas dissector facilitate the procedure and minimize tissue dissection.

Minimally-Invasive Vasectomy (MIV). The term "minimally invasive vasectomy" includes any vas isolation procedure, including the NSV technique, which incorporates two key surgical principles.39,224

1. Small (≤10 mm) openings in the scrotal skin, either as a single midline opening or as bilateral openings

2. Minimal dissection of the vas and perivasal tissues, which is facilitated by using a vas ring clamp and vas dissector or similar special instruments

The three finger technique described in Appendix A for immobilizing the vas or for making the skin opening has been modified slightly by various surgeons using MIV techniques other than the strict NSV technique. These variations include the use of the thumb rather than the middle finger behind the scrotum and other modifications of finger placement, bilateral skin openings or scrotal skin opening(s) made before grasping the vas with the vas ring clamp. 

MIV isolation techniques utilize either an open access approach or a closed access approach. In the open access approach, the skin opening(s) are made before the vas ring clamp or similar instrument is applied to the vas. In the closed access approach, the vas ring clamp or similar instrument is applied around the vas, perivasal tissue and overlying skin before the skin opening(s) is (are) made. The vas ring clamp and vas dissector are not required to perform MIV but are always very helpful.126 Other small or specially designed instruments may be used successfully to isolate the vas.39,126,224 Open access is sometimes necessary for men with thick scrotal skin or other anatomy that makes closed access difficult or impossible.

Other Important Points of Surgical Technique.

Single midline or bilateral incisions. The use of one midline or bilateral scrotal skin openings should be based on the surgeon's preference. One large observational study (N=1,800) compared single incision to double incision procedures. Fewer adverse events were reported with a single incision and the procedure time was reduced, but no statistical testing was performed.225 The Panel opinion is that there is no clear advantage to making one or two skin openings. The choice between midline and bilateral incisions should be left to the clinical judgment of the surgeon performing vasectomy.

Site of incision(s). For a midline approach, the scrotal skin opening should be made just below the penoscrotal junction or midway between the penoscrotal junction and the top of the testes. For a lateral approach, some experts recommend that the scrotal skin opening should be made at the level of the penoscrotal junction or higher.Scrotal skin openings for vasectomy should be positioned to provide access to the straight portion of the vas. Higher openings allow better access to the straight portion of the vas, make it easier to perform mucosal cautery and create longer vas remnants on the testicular side of the vasectomy. The opinion of the Panel is that occlusion of the vas is more easily performed in the straight portion than in the convoluted portion of the vas. In addition, occlusion of the vas in its straight portion may facilitate the performance of the anastomosis during vasovasostomy if reversal of the vasectomy is requested later.

Insuring that one vas is not occluded twice. For a single-incision vasectomy, the surgeon should ensure that the same vas is not isolated and occluded in two locations, leaving the other vas unoccluded. A gentle tug on each vas during isolation will cause the ipsilateral testis to move.226

Guideline Statement 6

Isolation of the vas should be performed using a minimally-invasive vasectomy (MIV) technique such as the no-scalpel vasectomy (NSV) technique or other MIV technique. Standard

Discussion


Vas Occlusion

Background Information about Vas Occlusion

In the US, virtually all techniques of vasectomy use complete division of the vas with or without excision of a segment of the vas. Following division of the vas, the divided vasal ends may be separated by one of several techniques and/or the flow of fluid and sperm within the vas lumen may be blocked by one of several methods. There is only one technique of vas occlusion, non-divisional extended electrocautery or the Marie Stopes International technique (see below), which does not use division of the vas. This technique is rarely, if ever, used in the United States. Therefore, in this guideline, vas occlusion means that the vas has been completely divided with or without excision of a vas segment, unless otherwise noted. Further, in this document, division/excision (D/E) means that the vas is divided and that a segment may or may not be excised. The panel found no consistent evidence indicating that division with excision of a short vas segment (< 4 cm) is preferable to division without excision of a vas segment.

Vasectomy effectiveness can be defined as either contraceptive effectiveness, which is the absence of pregnancy, or occlusive effectiveness, which is demonstrated by the finding on PVSA of azoospermia or of RNMS, as defined in a subsequent section of this Guideline. For definitions, see Table 4.

Table 4: Definitions for Vas Occlusion Methods

Contraceptive effectiveness: The absence of pregnancy.

Division/excision: Division with or without excision of a vas segment.

Fascial interposition (FI): Placing a layer of the vasal sheath (internal spermatic fascia) between the two severed ends of the vas in order to cover one end, but not the other end, with the vasal sheath.

Folding back: A method of folding and suturing each divided vas end on itself to prevent the two cut ends from facing each other.

Marie Stopes International (MSI) (non-divisional extended electrocautery technique of vas occlusion): The method used by Marie Stopes International (MSI) in the United Kingdom and its international clinics. This method utilizes electrocautery to destroy approximately 2.5 to 3.0 cm of the anterior wall of the vas, the mucosa and a part of the posterior wall of the vas without dividing the vas. This method is rarely, if ever, used in the US.

Mucosal cautery (MC): Application of thermal or electrical cautery to the vasal mucosa via intraluminal positioning of the cautery device to create a luminal plug of scar tissue without creating full-thickness thermal damage to the vas after division/excision of the vas

Occlusive effectiveness: Azoospermia or RNMS without any motile sperm at any time after vasectomy.

Open ended vasectomy: Division/excision with the use of fascial interposition to cover one end of the divided vas combined with occlusion of the abdominal end of the divided vas without occlusion of the testicular end.

Vasectomy effectiveness: Contraceptive or occlusive effectiveness.

The most commonly utilized vasectomy occlusion techniques are the following:

Fascial interposition (FI) is the technique of placing a layer of the internal spermatic fascia between the two divided ends of the vas. The fascial layer may be placed over the testicular or the abdominal end. Typically it is combined with other techniques such as ligation and excision or mucosal cautery.

Ligation means occlusion of the vas with ligatures with division/excision of the vas between the occluded points and with or without FI. The number of ligatures on each end of the divided vas varies between one (most common) and three. The length of the vas segment excised is most commonly approximately 1 cm but varies between 0 and 5 cm.

Clips means occlusion of the vas with clips with division/excision of the vas between the occluded points and with or without FI. The number of clips placed on each end of the divided vas is usually one or two but may be more. The length of the vas segment excised is most commonly approximately 1 cm.

Folding back is the technique of folding and suturing each divided vas end on itself to prevent the two cut ends from facing each other.

Mucosal cautery (MC) is the technique of applying thermal or electrical cautery to the mucosa of the cut ends of the vas to destroy the vasal mucosa while avoiding or minimizing damage to muscle layers. The goal of MC is to create a plug of scar tissue which occludes the vas lumen. The length of the cauterized segment varies from a few mm to 1.5 cm. MC may be combined with excision of a vas segment, folding back or FI. Cauterizing the mucosa while simultaneously limiting cautery damage to the muscular layer of the vas prevents sloughing of the cauterized portion of the vas, which could occur if its full thickness is destroyed by cautery. 

Non-divisional extended electrocautery technique of vas occlusion (Marie Stopes International technique) consists of electrocoagulation of the full thickness of the anterior wall and a partial thickness of the posterior wall of the vas for a length of approximately 2.5 to 3 cm without dividing the vas.29,153 It is the only technique which does not completely divide the vas. It uses monopolar electrocautery delivered by a Hyfrecator through a reusable needle. The technique was developed by Marie Stopes International in London (United Kingdom) as a vasectomy technique that could be easily disseminated, particularly in Third World conditions.153

Open-ended vasectomy is the technique of leaving the testicular end of the divided vas unoccluded while occluding the abdominal end. The hypothetical aims of this technique are 1) to prevent or reduce post-vasectomy pain by decreasing back pressure in the epididymis46 and 2) to allow the formation of a sperm granuloma at the transected testicular end of the vas, which some experts speculate might increase the chance of success of vasectomy reversal.46,150 When open-ended vasectomy is performed, FI is used to prevent recanalization.

Challenges in Interpreting the Evidence. The Panel undertook review of the vas occlusion literature with the goal of identifying with a high level of certainty specific techniques that consistently produce occlusive effectiveness. However, the vas occlusion literature suffers from serious methodological flaws that reduce certainty regarding conclusions about the relative efficacy of various occlusion techniques. These flaws include failure to identify whether enrollment is comprised of consecutive or selected patients; failure to obtain at least one PVSA in large percentages of vasectomized men, resulting in incomplete information regarding vasectomy outcomes; lack of information about follow-up protocols; unclear criteria for vasectomy failure; wide variations in follow-up duration; very short periods of follow-up duration and, possibly, failure to report series that had high failure rates. Two reports showed uncertain significance.25,45 One reported on a series of 14,047 vasectomies among which six men reported late recanalization with pregnancy. It is not clear from this report exactly how many couples were followed for pregnancy occurrence. In the absence of this information, it is not possible to conclude with certainty that the pregnancy failure rate is 6 in 14,047; the pregnancy failure rate may be higher if pregnancy data were not available for all patients. The other study reported no cases of sperm persistence and no pregnancies in 6,248 vasectomy patients. Because the number of patients who were followed and the timing of follow-up are not detailed in this paper, it is not possible to know whether successful vasectomy occurred in 6,248 men or in some number less than 6,248. Methodologically strong studies of occlusion technique effectiveness that would result in a high level of certainty regarding findings are characterized by the following:

  • Randomized controlled trial procedures
  • Enrollment of consecutive patients
  • Clearly described technique of vas occlusion
  • Standardized PVSA protocol
  • Clearly described criteria for PVSA failure
  • PVSA data on all patients for a minimum of six months post-vasectomy
  • Follow-up regarding pregnancy for a minimum of one year after vasectomy
  • Studies with sufficient sample size to allow precise estimation of effects

None of the studies reviewed by the Panel met all of these criteria, and only three studies met a majority of these criteria. This resulted in assigning Grade C as the strength of evidence for the body of literature on the efficacy of vas occlusion. Given the limited certainty associated with the use of Grade C evidence, the Panel focused on identifying methods of vas occlusion that produce consistent findings, including acceptably low failure rates, across multiple studies with large numbers of patients.  Four methods of vas occlusion that appear to be consistently reliable with regard to contraceptive and occlusive effectiveness were identified: (1) MC with FI and without the use of ligatures or clips on the vas; (2) MC without FI and without the use of ligatures or clips on the vas; (3) open ended vasectomy leaving the testicular end unoccluded while using MC of the abdominal end of the vas with FI; and (4) the Marie Stopes International method of vasectomy with extended non-divisional electrocautery of the vas. Based on this analysis of the literature, the Recommendations below were created. The Panel acknowledges that, in creating an evidence-based guideline, these Recommendations are necessarily based on the data that are available in the medical literature. The panel recognizes that there may be other techniques of vas occlusion that are reliable in producing occlusive effectiveness, even though detailed reports of the results of such occlusive methods have not been published.

Guideline Statement 7

The ends of the vas should be occluded by one of three divisional methods:

  1. Mucosal cautery (MC) with fascial interposition (FI) and without ligatures or clips applied on the vas;
  2. MC without FI and without ligatures or clips applied on the vas;
  3. Open ended vasectomy leaving the testicular end of the vas unoccluded, using MC on the abdominal end and FI;

OR by the non-divisional method of extended electrocautery. Recommendation

Discussion


Guideline Statement 8

The divided vas may be occluded by ligatures or clips applied to the ends of the vas, with or without FI and with or without excision of a short segment of the vas, by surgeons whose personal training and/or experience enable them to consistently obtain satisfactory results with such methods. Option

Discussion


Guideline Statement 9

Routine histologic examination of the excised vas segments is not required. Expert Opinion

Discussion


Post-Operative Practice

Background Information About Patient Follow-Up and Post-Vasectomy Semen Analysis

PVSA is used to confirm the effectiveness of a vasectomy postoperatively (for definitions, see Table 6). Vasectomy effectiveness can be defined as either contraceptive effectiveness or occlusive effectiveness. The standard definition of contraceptive effectiveness is the absence of pregnancy. The standard definition of occlusive effectiveness is post-vasectomy azoospermia. However, some men fail to achieve azoospermia after vasectomy yet never father a pregnancy. For example, one study found sperm in the semen of 18 of 186 (9.7%) men prior to vasectomy reversal.251 The average time since vasectomy was 10.7 years and no pregnancies occurred in the partners of these 18 men. Thus the definition of occlusive effectiveness should not be restricted to azoospermia but should include those men whose PVSAs show rare non-motile sperm (RNMS, or ≤100,000 non-motile sperm/mL) and no sperm motility.

Vasectomy failure. Vasectomy failure is the occurrence of pregnancy or failure to achieve azoospermia or RNMS after a reasonable period of time following vasectomy. Vasectomy failure may be a technical failure resulting from a surgical error such as occluding one vas twice without occluding the other vas or failure to identify the very rare situation of vas duplication on one side. Technical failure is characterized by persistently normal or nearly normal motile sperm counts and sperm motility after vasectomy. Vasectomy failure also may result from recanalization at the vasectomy site.

Recanalization following vasectomy should be suspected if motile sperm or rising sperm concentrations are seen after a routine PVSA has shown azoospermia or RNMS. Recanalization can be either transient or persistent based on the results of serial PVSAs. It is impossible to know the true incidence of late recanalization because PVSA is rarely repeated after a PVSA shows azoospermia or RNMS. Pregnancy due to recanalization is estimated to occur after approximately 1 in 2000 vasectomies or less often.25-29 The incidence of recanalization is very likely greater than the reported rate of pregnancy after post-vasectomy azoospermia because not all recanalizations result in pregnancy.

Table 6: Definitions for Post-Vasectomy Semen Analysis (PVSA)

Azoospermia: Absence of sperm during microscopic exam of at least 50 Hpfs in a single well mixed, uncentrifuged semen specimen.

Rare non-motile sperm (RNMS): Presence of ≤100,000 non-motile sperm/mL based on microscopic exam of at least 50 Hpfs in a single well mixed, uncentrifuged post-vasectomy semen specimen assuming no motile sperm are observed

Recanalization: A histologic diagnosis that shows reconnection of the vas ends, either directly or by microcanaliculi, after vasectomy. Recanalization can be suspected clinically based on PVSA results or after an unexpected post-vasectomy pregnancy if a previous PVSA showed azoospermia or RNMS.

Sterility: The inability to cause pregnancy

PVSA Principles. Controversies in the timing, technique, reporting and significance of PVSA include the following:

  • When the first PVSA should be done
  • Number of PVSAs that should be done
  • Necessity for the PVSA to be performed on a fresh specimen
  • Necessity for centrifugation of the specimen
  • Reliability of PVSAs sent for analysis by mail
  • Reliability of PVSA home test kits
  • Criteria of vasectomy success defined by absolute azoospermia or the presence of RNMS
  • Volume of semen that should be examined
  • Number of semen aliquots that should be examined
  • Number of high power fields that should be examined

The aim of a PVSA is to confirm occlusive effectiveness and to advise a patient that he can safely rely on his vasectomy for contraceptive purposes. Practical principles relevant to PVSA are as follows:

  • The PVSA protocol should be as simple as possible to encourage patient compliance.
  • The PVSA should allow for confirmation of occlusive effectiveness as soon as possible after vasectomy while simultaneously minimizing the number of PVSAs required to document occlusive effectiveness.
  • The PVSA protocol should confirm occlusive effectiveness with the highest possible level of certainty.
  • Patients should be informed that post-vasectomy pregnancies are rare but have been documented even after multiple serial PVSAs reveal azoospermia.

Considering these principles, a vasectomy should be considered successful as soon as a PVSA confirms that the risk of pregnancy is sufficiently low to allow the patient to rely on the vasectomy alone for contraception. Conversely, a vasectomy should be considered a failure – or not yet a success – when a man needs to use another contraceptive method or needs to repeat the surgical procedure before relying on his vasectomy.

Sperm Clearance After Vasectomy. Sperm clearance after vasectomy is time dependent with both large inter-individual variations as well as variability across published reports, including those that used the same vas occlusion technique. Inter-individual variation may result from differences in reproductive anatomy and possibly patient age. Sperm may persist in the ejaculate for many months after vasectomy. Such persistence may be due to residual sperm in the seminal vesicles or ampullae of the vasa, 252 recanalization, or, very rarely, a failure to have performed the vasectomy on one vas. The main reason for the presence of non-motile sperm is probably that residual sperm in the seminal vesicles or ampullae of the vasa are slowly released from the reproductive tract.252 There are wide variations in the clearance of residual sperm in the seminal vesicles or ampullae of the vasa among men due to inter-individual differences in the anatomy of these structures.252 However, in most men, either no sperm or only small numbers of non-motile residual sperm in the PVSA are seen at three months or later after vasectomy. Nevertheless, some men have continued to have sperm or sperm parts in the semen which have been found for as long as 31 years post-vasectomy.251,253

With regard to age, several studies have suggested that sperm clearance may take longer in older men compared to younger men.10,15,235,254,255 For example, Marshall and Lyon (1972) reported that younger patients may achieve azoospermia with fewer ejaculations than older patients.256 Marwood (1979) reported that the frequency of ejaculation affected time to azoospermia more in older than in younger men, with a frequency of three times a week associated with rapid clearance regardless of age.257

The published literature also contains mixed results regarding the relationship between sperm clearance and number of ejaculations. After 10 ejaculations, rates of azoospermia ranged from 43% to 50%.34,232,258 After 12 ejaculations, rates of azoospermia have been reported as 66%256 and 88%.259 However, one study with relatively complete follow up showed that only 44% of patients were azoospermic after 20 ejaculations.242 Many practitioners recommend that the first PVSA should be done after 20 ejaculations. The opinion of the Panel is that rates of azoospermia related to number of post-vasectomy ejaculations are too variable to be useful in determining when to do the first PVSA.

Variability across published reports in sperm clearance rates may result from surgical technique used to occlude the vas; differences in criteria for vasectomy success (e.g., one, two or three azoospermic specimens); variations in PVSA laboratory techniques and reporting; small sample sizes in some studies and varying time points at which PVSA was performed.  In addition, in many studies, although patients were instructed to report at specific intervals post-vasectomy, some report at later intervals. This inconsistency between requested PVSA timing and actual PVSA timing creates uncertainty regarding true sperm clearance rates because not all articles clearly indicate when patients actually returned for PVSAs. In addition, in most studies about a third of patients do not return for the requested PVSAs.260 The lack of complete follow-up data also creates uncertainty regarding true sperm clearance rates.

Another source of variation in the proportion of men achieving azoospermia is variation in the laboratory techniques used for PVSA and for reporting of PVSA results. Rigorous semen examination including centrifugation and examination of hundreds of microscopic fields is likely to find more sperm than less rigorous laboratory techniques. If the physician sends PVSA specimens to a commercial laboratory, the physician should request that the laboratory perform the PVSA without centrifugation because centrifugation may reduce or eliminate sperm motility (see below). The physician should also request the laboratory to report both the presence or absence of sperm and the presence or absence of sperm motility. If only non-motile sperm are present, the physician should request the laboratory to report the number of non-motile sperm per mL. If no sperm are found in the uncentrifuged specimen, then ideally the laboratory should report that the presence of sperm is "below the limit of detection," although most laboratories report "azoospermia" in this situation.

Clearance of motile sperm. Clearance of motile sperm is much more rapid than clearance of non-motile sperm. Older studies suggest all motile sperm disappear within three weeks after vasectomy.261,262 More recent studies confirm that when MC and FI are combined to occlude the vas, essentially all motile sperm have disappeared by five to six weeks233 with only 1% of men continuing to show motile sperm.258 At 7 to 14 weeks, this proportion drops to 0.4% and by more than 14 weeks post-vasectomy, no motile sperm were observed.258

Numerous studies have reported the reappearance of nonmotile sperm28,263-265 and even motile sperm22,28,35,42,256,263,266 after azoospermia was confirmed, with most studies reporting this phenomenon in small numbers of patients (i.e., < 1%). However, it should be noted that many patients in these studies did not return for PVSAs or did not return for a second PVSA when requested, making the true rates of sperm reappearance (both motile and non-motile) unclear.

PVSA Analytic Techniques: Centrifugation of semen samples for PVSA is unnecessary. Laboratory techniques, especially centrifugation, influence the presence or absence of azoospermia observed in a PVSA. Over the past two decades, data suggest that centrifugation leads to the identification of more men with small numbers of sperm. This means that correspondingly fewer men are reported with azoospermia, leading to increased follow-up testing and more repeat vasectomies, some of which may not be necessary. 267

The British Andrology Society and the 1992 (3rd edition) and 1999 (4th edition) of the World Health Organization laboratory manual for the examination of human semen and sperm-cervical mucus interaction specifically recommended centrifugation of azoospermic semen samples as part of the routine post-vasectomy semen analysis. 268 However, centrifugation is not necessary to confirm that only rare non-motile sperm are present. The 2010 (5th edition) WHO laboratory manual for the examination and processing of human semen suggests relying on careful examination of an uncentrifuged specimen, similar to a recently PVSA protocol proposed by Korthorst (2009).244,269 The 2010 (5th edition) WHO laboratory manual states in Section 2.10.3, page 46, "When motile spermatozoa are sought (e.g., in a post-vasectomy semen sample), diluting the specimen in fixative or high-speed centrifugation of spermatozoa must be avoided."269 One group examined uncentrifuged azoospermic semen specimens compared with centrifuged specimens (n=2,014 samples) and concluded that uncentrifuged semen analysis is a reliable method of identifying samples with > 100,000 sperm/ml.270 The sensitivity of the uncentrifuged sample was 99.3% and the negative predictive value was 99.8%.

Because centrifugation may interfere with sperm motility269 and clinically relevant numbers of sperm can be identified without centrifugation, a surgeon should request a clinical laboratory not to perform centrifugation for a PVSA.

Office examination of uncentrifuged post vasectomy semen samples. In the US, CDC regulations implementing the 1988 Clinical Laboratory Improvement Act (CLIA) (42 CFR 493.19) distinguish provider-performed microscopy (PPM) analysis from that in laboratories performing tests of high complexity. These regulations allow for semen analysis in a doctor's office, i.e., "provider performed microscopy," as long as the reported result is qualitative, i.e., "limited to the presence or absence of sperm and detection of motility." Thus US physicians are permitted to conduct PVSA in their offices, but they are not allowed to determine sperm concentration unless the office laboratory has a high-complexity level of CLIA certification. There is now interest in developing a method of estimating the number of sperm per mL of semen from the number of sperm per Hpf found in a PVSA. Such a method would allow vasectomy surgeons to correlate the number of sperm per Hpf in PVSAs which do not show azoospermia to various concentrations of sperm/mL.

Self-PVSA Testing. A self-PVSA home test has been approved by the FDA and is available for clinical use. This test is sensitive to sperm counts >250,000/ml,271 but the test does not assess for sperm motility. If two tests are performed and both are negative, then the negative predictive value of a sperm count >250,000 sperm/mL is 99.9%. However, the 250,000 sperm/mL cut-off is significantly higher than the cut-off most commonly used to declare a man sterile after vasectomy. The most commonly used cut-off in the literature and the definition of vasectomy success used in this guideline is ≤100,000 non-motile sperm/mL. Furthermore, no other studies have shown that clearing men at this cut-off without evaluating for motility is reliable enough to recommend discontinuation of contraception, and no studies have followed patients who used the test to assess for the risk of unanticipated pregnancy. In addition, it has been suggested that a home PVSA test might increase patient compliance with PVSA instructions, but improved patient compliance has not yet been studied or proven.

Because the test results are read by the patient, the surgeon must instruct the patient on all aspects of the test prior to its use. To avoid potential legal problems, careful instruction is essential to ensure that the patient will use the test in a valid manner. The disclosures must include how to set up the test, how to read the final result and the relative risks of pregnancy. Given this requirement and the lack of long-term follow-up data on patients who have used the test, the opinion of the Panel at this time is that, although this test may have potential value that may be proven in the future, there are insufficient data for the panel to come to a conclusion regarding its use in clinical practice.

Guideline Statement 10

Men or their partners should use other contraceptive methods until vasectomy success is confirmed by PVSA. Clinical Principle

Discussion


Guideline Statement 11

To evaluate sperm motility, a fresh uncentrifuged semen sample should be examined within two hours after ejaculation.  Expert Opinion

Discussion


Guideline Statement 12

Patients may stop using other methods of contraception when examination of one well-mixed, uncentrifuged fresh post-vasectomy semen specimen shows azoospermia or only rare non-motile sperm (RNMS or ≤ 100,000 non-motile sperm/mL). Recommendation

Discussion


Guideline Statement 13

Eight to sixteen weeks after vasectomy is the appropriate time range for the first PVSA. The choice of time to do the first PVSA should be left to the judgment of the surgeon. Option

Discussion


Guideline Statement 14

Vasectomy should be considered a failure if any motile sperm are seen on PVSA at six months after vasectomy, in which case repeat vasectomy should be considered. Expert Opinion

Discussion


Guideline Statement 15

If > 100,000 non-motile sperm/mL persist beyond six months after vasectomy, then trends of serial PVSAs and clinical judgment should be used to decide whether the vasectomy is a failure and whether repeat vasectomy should be considered. Expert Opinion

If non-motile sperm are present on the first PVSA in the surgeon's office, one or more repeat PVSAs should be performed in the surgeon's office laboratory to determine if azoospermia develops over time. If azoospermia is not achieved by six months after vasectomy, then a PVSA should be performed in a laboratory approved for high complexity semen testing. If the PVSA shows ≤100,000 non-motile sperm/mL and no motile sperm, then the couple may stop using other methods of contraception.

If the PVSA shows > 100,000 non-motile sperm/mL or any motile sperm, then further PVSA monitoring or repeat vasectomy may be considered. The Panel's opinion is that the decision to consider vasectomy a failure if >100,000 non-motile sperm/mL persist should be based on clinical judgment that includes the trend of sperm counts, the patient's preferences and the patient's tolerance for the risk of pregnancy.

Additional Important Points of Postoperative Practice.

After completion of a vasectomy, physicians should consider giving men a specific appointment for the first PVSA to improve compliance with follow-up. Based on 46 published studies reviewed in 49 papers, a median of 78% (range 33-100%) of men return for a single PVSA and a median of 73% (range 21-100%) are fully compliant with PVSA study protocols.13,22-28,30,34,35,37,38,52,131,134,137,138,142,144,170,181,231,232,235,237,242,243,253,256-265,277,280,282-288 Compliance rates varied greatly across studies and might be lower in clinical practice than in published studies. In the largest cohorts that appear typical of North American vasectomy practice, only about two thirds of men (between 55% and 71%) return for at least one PVSA.28,30,38,243,260,288

The number of tests requested (one or two) and the time at which samples were requested (one to two months vs. three to four months) do not appear to make a significant difference in compliance rates. When the second test was requested at three to four months post vasectomy, rates of full compliance were decreased somewhat compared to protocols where two tests were ordered within two months.289

One randomized controlled trial including 228 men evaluated the effectiveness of scheduling an appointment for the first PVSA versus simply asking men to return at two months post-vasectomy. In the appointment group 84% of men returned for semen analysis versus 65% in the no appointment group.290 The Panel suggests that the practice of scheduling a follow-up PVSA appointment should be left to the judgment of the individual clinician.

A postoperative visit with the surgeon specifically for physical examination of the scrotum is not routinely necessary. The results of the PVSA and/or the need for one or more additional PVSAs can be conveyed by telephone or other modes of communication. When giving PVSA results, men should be reminded that no contraceptive method, including vasectomy, is 100% effective. At this time, patients should be informed that there is always a remote risk of pregnancy even if azoospermia has been achieved. Each patient should know that if his partner becomes pregnant, he may have experienced a rare vasectomy failure and should return to his surgeon for a semen analysis. Even if a PVSA at such a time reveals azoospermia, a transient recanalization may have occurred with the subsequent disappearance of sperm from the semen, as shown by DNA studies on parents and the child in such situations.291

Most men whose partners become pregnant after vasectomy have motile sperm in the semen, but some are found to be azoospermic on multiple examinations following identification of the pregnancy. If a man reports that his wife has become pregnant and his semen analysis reveals azoospermia, then the physician should inform him that the pregnancy could have been due to a transient recanalization despite the semen analysis results. A number of case reports have confirmed paternity based on genetic testing even though the men previously had multiple semen analyses showing azoospermia, i.e., sperm counts below the limit of detection.291-293 Patients may be informed that genetic analysis to document paternity is available.

Future Research

One benefit of a systematic review is to illuminate deficits in the scientific knowledge base, the amelioration of which would move the field forward and allow for advances in clinical care. The Panel identified the following areas for future research efforts.

Preoperative Evaluation and Counseling

  • Identification of the information most important to patients and partners during and after the decision-making process and, in particular, the type of information and information presentation that is most effective to gain the patient's attention, maximize understanding and minimize post-procedure regret and dissatisfaction. One recent study addressed the value of a patient decision aid before and after the procedure and concluded that it was helpful in both a comprehensive and an abridged version.294
  • The percentages of couples who select vasectomy vs. tubal ligation when fully informed regarding both options. This information is central to understand the extent to which the relative under-utilization of vasectomy in the US is a function of lack of understanding of the procedure.
  • The selection of vasectomy or tubal occlusion depending upon whether the patient/couple sees a gynecologist or urologist first.
  • Whether rates of dissatisfaction and/or regret are related to the inclusion of the spouse or partner in the preoperative counseling process.
  • Do men and partners of men considering vasectomy believe that vasectomy is a family or an individual decision?

Anesthesia

  • Pain levels (measured with visual analog scales) associated with the use of smaller gauge vs. larger gauge needles for local anesthesia administration, with the use of a mini-needle technique (30-32 gauge needle with 3 cc xylocaine) compared to the Li anesthetic block technique (25-27 gauge needle with 10 cc xylocaine) and the use of mini-needles compared to jet injection.
  • Whether or not topical anesthetic cream application before injection of local anesthetic reduces the amount of pain (measured by a visual analog score). If the pain of local anesthetic injection is reduced, the extent to which topical anesthetic cream before local anesthetic injection reduces the pain of injection as well as the pain of the vasectomy.
  • Pain level during local anesthesia administration as opposed to during the vasectomy procedure itself.
  • Whether or not application of a topical cutaneous spray such as ethyl chloride, cocaine or other products prior to injection of local anesthetic reduces the pain of injection.

Vas Isolation

  • Whether pain is reduced when an NSV or MIV vas isolation technique is used compared to a conventional technique.
  • Intraoperative and post-operative pain levels and surgical complications (e.g., at one, two and four weeks) with an MIV technique compared to a conventional vasectomy.
  • The incidence of failed vasectomy with use of a single midline incision compared to bilateral incisions.
  • Information regarding how the technical skills required to perform NSV are learned and translated into practice and to what extent practitioners reporting that they perform NSV are adhering to each of the requirements of the technique.
  • The incidence of early post-vasectomy scrotal hematoma and abscess formation according to the method of vas isolation.

Vas Occlusion

  • Methodologically robust (e.g., well-designed prospective observational studies and RCTs) are needed of large cohorts in developed countriesthat compare occlusive techniques with regard to surgical complication rates, post-vasectomy pain and occlusive and contraceptive effectiveness at short-, medium- and long-term follow up points.
  • Evaluation of the effectiveness of thermal cautery vs. electrocautery for vas occlusion.
  • RCTs to evaluate the occlusive effectiveness and complication rates associated with cautery and FI vs. cautery alone, open versus closed testicular end with FI and cautery of the abdominal side and complications including anti-sperm antibodies.
  • Reliable techniques for applying cautery to the vasal mucosa and avoid damage to the vasal muscularis.
  • Information regarding the potential value and possible complications from the addition of folding back to any technique.
  • Whether postoperative bleeding complications are more common if FI is performed than if FI is not performed.
  • The development of percutaneous occlusion techniques.

Post-Vasectomy Follow-up

  • More rigorous study of the prevalence of azoospermia and RNMS related to the method of vas occlusion at various time intervals after vasectomy (e.g., at weeks 6, 9, 12, 16, 20 and 24).
  • Study of why some men have RNMS for substantial intervals post-vasectomy (e.g., three, six, nine months) while others do not.
  • Information about the prevalence of paternity at various post-vasectomy time intervals as long as 5 to 10 years.
  • Contraceptive effectiveness at different PVSA thresholds (including varying levels of RNMS).
  • Whether the PVSA thresholds of commercially available home test kits are sufficient to ensure contraceptive effectiveness.
  • How couples who desire to have more children after a vasectomy choose between vasectomy reversal and sperm retrieval with IVF/ICSI and the percentage of couples choosing each technique.
  • Comparisons of PVSA results when the analysis is done by physicians in office laboratories certified for provider performed microscopy compared to results of commercial laboratories certified for high complexity testing.
  • Comparison of the number of sperm/HPF between standard light microsopy and phase contrast microsopy.
  • Patient preferences for the timing of PVSA with regard to achieving earlier clearance vs. the need for more than one PVSA.
  • Investigations of post-vasectomy testicular changes (i.e., histologic changes in the seminiferous tubules and in spermatogenesis, electron microscopic changes of interstitial fibrosis) and how they may correlate with both post-vasectomy antisperm antibody status and with vasectomy reversal outcomes.
  • The incidence of serum antisperm antibodies as determined by immunoglobulin A, G and M testing after vasectomy and how they affect fertility rates after vasectomy reversal and after sperm retrieval with IVF/ICSI (including sperm surface antibody studies in seminal plasma after vasectomy reversal).

Complications

  • Methodologically rigorous studies to provide accurate rates of early post-vasectomy hematoma, wound infection and scrotal abscess formation.
  • Studies that distinguish between post-vasectomy pain due to epididymal congestion or epididymal sperm granuloma (resulting from rupture of the epididymal tubule caused by back pressure below the level of the vasectomy) vs. pain due to true bacterial epididymitis.
  • Studies of various imaging modalities that allow the accurate diagnosis of the cause of post-vasectomy epididymal pain.
  • Incidence of chronic post-vasectomy pain according to standardized scales starting at three to six months and continuing until up to three to five years post-vasectomy.
  • Incidence of chronic pain of differing severity, the percentage of patients who feel that their quality of life has been impacted by the pain, the percentage of patients who seek medical help for relief of such pain, the percentage who undergo some type of surgical procedure for pain relief and the success rate of the various procedures for relieving the pain.

Tools and Resources

Abbreviations

Abbreviations

ASA(s)

anti-sperm antibodies

AUA

American Urological Association

cc

cubic centimeter

CHD

coronary heart disease

CI

confidence interval

CLIA

Clinical Laboratory Improvement Act

cm

centimeter

CV

conventional vasectomy

D/E

division with or without excision of a vas segment

ES

evidence strength

FI

fascial interposition

FSH

follicle-stimulating hormone

Hpf(s)

high power field(s)

ICSI

intracytoplasmic sperm injection

IVF

in vitro fertilization

LE

ligation and excision

LH

luteinizing hormone

MIV

Minimally-invasive vasectomy

mL

Milliliter

mm

millimeter

MSI

Marie Stopes International

NSV

no-scalpel vasectomy

OR

odds ratio

PPA

Primary Progressive Aphasia

PPM

provider-performed microscopy

PVSA

post-vasectomy semen analysis

RCT

randomized controlled trial

RNMS

rare non-motile sperm

RR

relative risk

µL

Microliter

US

United States

VAS

visual analog scale

WHO

World Health Organization

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