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New WHO Manual 6th ed.

The 6th edition of the “WHO Laboratory Manual for the Examination and Processing of Human Semen” was published in 2021. The link WHO laboratory manual for the examination and processing of human semen takes you to the WHO website, which offers a free download of the manual in PDF format.

One of the changes in the manual is the return to differentiation into 4 motility categories.

a) rapidly progressive (25 µm/s): spermatozoa moving actively, either linearly or in a large circle, covering a distance, from the starting point to the end point, of at least 25 µm (or ½ tail length) in one second,
b) slowly progressive (5 to < 25 µm/s): spermatozoa moving actively, either linearly or in a large circle, covering a distance, from the starting point to the end point, of 5 to < 25 µm (or at least one head length to less than ½ tail length) in one second;
c) non-progressive (< 5 µm/s): all other patterns of active tail movements with an absence of progression – i.e. swimming in small circles, the flagellar force displacing the head less than 5 µm (one head length), from the starting point to the end point
d) immotile: no active tail movements.

For QuaDeGa purposes, however, we maintain the classification of spermatozoa as listed in the 5th edition of the WHO Manual:

PR: all spermatozoa moving actively, either rapidly or slowly,
NP: all other patterns of active tail movements with an absence of progression,
IM: immotile spermatozoa.

QuaDeGA is performed on the basis of the RiLi-BÄK (Guideline of the German Medical Association for Quality Assurance of Laboratory Medical Examinations), especially part B4, which regulates the ejaculate examinations. In the RiLi-BÄK, under point 2.1.2, page A25, motility is categorized into the three categories of progressively motile, locally motile and immotile. As long as this point of the guideline is not changed, the QuaDeGA test will continue to be based on these specifications.

Therefore, at present the QuaDeGA ring trials remain unchanged. As soon as there is a change in the RiLi-BÄK, we will inform you.