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Published on: November 29, 2018
Normal reference ranges for semen quality and their relations to fecundity
1University Department of Growth and Reproduction, Rigshospitalet, Copenhagen DK, Denmark. nes@rh.dk
Asian Journal of Andrology
|January 30, 2010
Summary
New guidelines lower the normal sperm concentration threshold, potentially hindering fertility diagnosis. This change may prevent many subfertile men from receiving essential andrological assistance.
Area of Science:
- Reproductive medicine
- Andrology
- Semen analysis
Background:
- Male fecundity is linked to sperm concentration.
- Studies indicate a decline in fertility below 40 million spermatozoa/mL.
- Previous World Health Organization (WHO) guidelines set the lower limit at 20 million spermatozoa/mL.
Purpose of the Study:
- To evaluate the impact of revised World Health Organization (WHO) semen analysis guidelines.
- To assess the implications of lowering the lower reference limit for sperm concentration.
Main Methods:
- Analysis of recent scientific literature on male fecundity and sperm concentration.
- Review of World Health Organization (WHO) guidelines for semen analysis.
Main Results:
- Male fertility declines progressively with sperm concentrations below 40 million spermatozoa/mL.
- The new WHO guidelines recommend a lower cutoff of 15 million spermatozoa/mL.
- This reduction risks misclassifying subfertile men.
Conclusions:
- Lowering the sperm concentration cutoff may lead to a significant number of subfertile men being overlooked.
- Reduced access to andrological help for a large population of men is a potential consequence.
- Revisiting the WHO guidelines is crucial to ensure accurate male fertility assessment.
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