Please reference the the following comparison table of WHO 4th and 5th Morphology criteria and Dr. Menkveld’s (the author of publications used by the WHO) presentation at ESHRE SIG-Andrology Campus Meeting, 2009.
Based on this comparison and Dr. Menkveld’s presentation, the following conclusions can be drawn:
• In the Dr. Menkveld presentation, no WHO 5th vs. WHO 4th Morphology criteria differences are mentioned, only a lower reference limit. Strict criteria is used for morphology assessment and grading in both manuals.
• The concept of normal spermatozoon by WHO 4th and 5th manuals are the same.
• Most of WHO 4th and 5th Morphology criteria are the same.
• There are the slight but not significant differences in some dimensional details that were updated in the WHO 5th manual.• The WHO 4th manual Morphology reference value was not final and was updated in the WHO 5th edition.
The overall conclusion is that the WHO 4th and 5th Morphology criteria are similar, as they are based on the same strict principles, similar guidelines and reference publications. As the WHO 4th and 5th criteria are similar, we did not conduct any additional study for the WHO 5th morphology algorithm and stayed with the same developed for the WHO 4th. Only the reference value was changed in the V-Sperm.