RE: Clinical relevance of routine semen analysis and controversies surrounding the 2010 World Health Organization criteria for semen examination

Dr. Sandro Esteves and collegues, from Brazil, performed on page xx at this issue of the International Braz J Urol an elegant review that discuss how the new World Health Organization (WHO) criteria for seminal parameters could affect the clinical management of men presenting with male infertility. The authors emphasized the factors that limit the use of seminal parameters as a surrogate for male fertility and also propose a template to be used for semen analysis reports to allow a better interpretation for clinicians. Biological proof of male sterility is only present in cases of azoospermia or in the presence of a complete lack of sperm motility. Since such cases of male sterility are uncommon, clinicians presume to obtain a clear indication of a man’s fertilizing potential from semen analysis. That would be finding a cutoff value in order to determine which number of sperm count, motility or morphology could better differentiate fertile patients from subfertile patients. The precise statistical test to find this “magical” number would be through a generation of a receiver operating characteristic curve which examined various cutoff values to determine one with high sensitivity, specificity and accuracy that would be superior in differentiating both populations. Unfortunately, the application of this test may be relevant in relation to certain clinical tests including levels of sodium or potassium in serum, but are unsuitable for seminal parameters because there is a significant overlapping distribution in the sperm characteristics between fertile and subfertile populations (1, 2). The definition of “normal” semen quality has changed over time (3, 4). The 2010 WHO guidelines have reduced the reference limits for seminal parameters, in the sense that the ‘normal’ reference range was defined as the one that covers 95% of a population (5). The current suggested reference values fail to satisfy clinical and statistical standards and pose the risk of misclassifying a subject’s true fertility status (2). Moreover, the introduction of these new values to the clinical practice is likely to result in a reclassification of many infertile couples (6). As an example, those couples previously classified as having male factor infertility with sperm parameters greater than the new reference limits, but less than the previous values, probably, will now be diagnosed as having unexplained infertility. Moreover, as the newest lower reference limits are even lower than the previous reference values, clinicians will likely be faced with an increased number of men presenting with treatable causes of infertility, as varicocele, and semen parameters within the “normal reference” values. Since the recommendation for varicocele treatment has been based on the results of routine seminal parameters, an important question has now risen: Should we perform a varicocele repair for an infertile Vol. 41 (1): 181-183, January February, 2015