The Sixth Edition of the WHO Manual for Human Semen Analysis: A Critical Review and SWOT Analysis

CAPSULE

Contributors: Christopher Ho, MD (Malaysia), Widi Atmoko, MD (Indonesia)

Semen analysis is a mainstay for initial evaluation among infertile men. Proper preparation, assessment, and interpretation are mandatory to avoid misdiagnosis or unnecessary treatment. After around 10 years since the last edition, the WHO released its newest sixth edition manual of semen examination and processing. The present article reviews the Sixth Edition of the WHO Manual for Human Semen Analysis,
including a thorough analysis of strengths, weaknesses, opportunities, and threats (SWOT)

What the 5th edition lacked; this 6th edition attempted to improve on. It includes adding new data from fertile men in Southern Europe, Asia, and Africa to increase the representativeness of all geographical areas. Nevertheless, there is still no representation from Saharan Africa or South America. This 6th edition also
acknowledges that the 5th percentile values of basic semen parameters alone are insufficient for accurate diagnosis of male infertility. However, this created a lack of reference threshold or decision internals to replace the 5th percentiles.

The manual introduces an updated laboratory technical guide on semen analysis, including comprehensive step-by-step procedures. For instance, it adopts the earlier classification of sperm motility, adds semen odor examination, and a detailed assessment of lower sperm concentrations. Some recommendations on quality control and quality assurance that can help guide optimum laboratory performance are provided in the manual.

In addition, sperm DNA fragmentation (SDF) and fluorescence in situ hybridization (FISH) are also introduced as extended tests of semen. SDF is considered the most discussed and promising addition in male infertility workup. Despite the introduction of SDF as an extended examination, there is still a lack of indication, criteria for interpretation and cut-off threshold values. Despite sufficient data saying otherwise, the 6th edition still considers oxidative stress (OS) tests as specialized and mainly research based procedures in the advanced test section.

The problem that can arise is that there are too many technical details and a lack of reference values in this 6th edition, which may put off clinicians from reading it. The lack of reference values may drive clinicians to use the 5th edition instead. More importantly, clinicians should consider multiple factors, such as the patient's clinical status and female factors in fertility assessment to provide a thorough diagnosis.

The changes in the sixth edition of the WHO manual of human semen examination and processing have offered a great understanding of how to carry out a proper semen analysis. However, there is room for updates and improvement. This review by GAF authors rightfully said that future research may help overcome weakness in this 6th edition to help produce a better edition in the future, especially with the help of SWOT analysis.

Considering that clinicians must evaluate the strengths and drawbacks of the existing manual and reach a reasonable decision specific to each patient's situation, the review has completely analyzed and broken down the gist of the 6th edition so eloquently that it is an excellent supplement for busy clinicians who do not have the time to sieve through too many pages of jargon.