Page 3 - CUA guideline: Vasectomy

Zini et al.

azoospermia at three months than no interposition (OR for possible scrotal bleeding or vaso-vagal reaction. It may
0.42 [0.26, 0.70]). 4,23,24 However, fascial interposition may be prudent to recommend that patients be driven home.
increase the complication rate of vasectomy. 25 Men should be instructed about proper wound and scrotal
Recommendation: Fascial interposition during vasectomy care and short-term physical limitations. Men should be told
is associated with a significantly higher rate of azoospermia how to collect the semen sample (completeness and type of
at three months than no interposition (Grade B). container) and reminded of the importance of submitting the
sample to the laboratory in a timely fashion (within 30‒60
Cautery vs. fascial interposition minutes after producing the sample). They should also be
told that semen samples should be collected after an absti-
In a comparative (case-control) study, cautery of the vas nence period of two or more days and no more than seven
was associated with a lower risk of failure (defined as >100 days, and maintained at body temperature before delivery
000 sperm in the ejaculate) than fascial interposition (1% to the laboratory. A list of local laboratories that perform
vs. 4.9%, OR 4.8 [1.6-14.3]). 3 proper post-vasectomy semen analysis should be given to
Recommendation: Cautery of the vas is associated with the patient. The men must be reminded to use other con-
a lower risk of failure (defined as >100 000 sperm in the traceptive measures until post-vasectomy semen testing has
ejaculate) than fascial interposition (Grade B). confirmed absence of motile sperm.
Arguably, the above findings on azoospermia rates are
somewhat confusing (“fascial interposition is better than no 5. Post-vasectomy semen testing
fascial interposition” and “cautery is better than fascial inter-
position”). However, the take-home message is that both The post-vasectomy semen analysis should be performed
cautery and fascial interposition are the best vas occlusion on the whole (unprocessed) semen and on the centrifuged
methods. semen to confirm the absence of low numbers of motile
sperm. The laboratory should give an estimation of sperm
3. Contraceptive efficacy of vasectomy concentration or numbers of spermatozoa observed per
high-power field (×400 magnification). 28-30
The early failure rate of vasectomy (presence of motile sperm It is important to recognize that compliance with post-
in the ejaculate at three to six months post-vasectomy) is vasectomy semen testing is a significant issue, with up to
in the range of 0.3‒9% and has been linked to operator 30% of men failing to submit a single sample. 31,32
experience and the technique used by the surgeon. Both
25
technical failure (e.g., missed vas deferens) and early recana- One vs. two post-vasectomy samples
lization of the vas deferens have been proposed as plausible
explanations. Surveys have shown significant variability in the post-
Late failure has been reported to be in the range of vasectomy testing protocols. Most agree that a single azo-
33
0.04–0.08% (approximately 1/2000 cases) and is defined ospermic semen sample is sufficient to deem the vasectomy
as the presence of motile spermatozoa in the ejaculate after effective. 30,34 However, because spermatozoa are detected
documented azoospermia in two post-vasectomy semen in 10‒40% of the three-month post-vasectomy samples
analyses. 7,26 In most cases, late failure is first identified as (the percent depends on the vasectomy technique and the
a pregnancy and later confirmed by semen analysis (docu- accuracy of the semen analysis), it may be necessary for up
menting presence of motile spermatozoa). to 40% of the men to submit a second semen sample. 25,35
The reappearance of sperm (mostly immotile) after docu- As such, requesting two semen samples at the onset may
mented azoospermia in two post-vasectomy semen samples be more efficient, as this may reduce the number of post-
may be much higher than 1/2000 according to the reported vasectomy counselling sessions (e.g., phone calls or office
identification of spermatozoa in nearly 10% of ejaculates visits), but this may also reduce the overall compliance. 32
from men undergoing semen assessment prior to vasectomy Recommendation: The evaluation of two post-operative
27
reversal. It is unlikely that the reappearance (or persistence) semen samples is a better predictor of success than the
of immotile sperm years after vasectomy is of clinical sig- evaluation of a single semen sample (Grade C).
nificance, as this has not been associated with documented
pregnancies. 28,29 Timing of post-vasectomy testing

4. Postoperative counselling Although most studies suggest that post-vasectomy testing
be conducted at three months after vasectomy, the issue
After the vasectomy has been performed, men should be remains debatable, with some studies suggesting earlier
told to remain in the clinic for 15‒20 minutes to be assessed examinations (with determination of failure based on the

E276 CUAJ • July-August 2016 • Volume 10, Issues 7-8