Sperm counts significantly declining in men from North America, Europe

[Nelson Vergel]

BACKGROUND
Reported declines in sperm counts remain controversial today and recent trends are unknown. A definitive meta-analysis is critical given the predictive value of sperm count for fertility, morbidity and mortality.





OBJECTIVE AND RATIONALE
To provide a systematic review and meta-regression analysis of recent trends in sperm counts as measured by sperm concentration (SC) and total sperm count (TSC), and their modification by fertility and geographic group.

“In this comprehensive meta-analysis, sperm counts whether measured by SC or TSC declined significantly among men from North America, Europe and Australia during 1973–2011, with a 50–60% decline among men unselected by fertility, with no evidence of a ‘leveling off' in recent years,” the authors concluded.

Reference

1. Levine H, Jørgensen N, Martino-Andrade A, et al. Temporal trends in sperm count: a systematic review and meta-regression analysis. Hum Reprod Update. 25 July 2017. https://doi.org/10.1093/humupd/dmx022

 

[Nelson Vergel]

Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries

AbstractBACKGROUND. Numerous studies have reported declines in semen quality and other markers of male reproductive health. Our previous meta-analysis repo

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This analysis is the first to report a decline in sperm count among unselected men from South/Central America–Asia–Africa, in contrast to our previous meta-analysis that was underpowered to examine those continents. Furthermore, data suggest that this world-wide decline is continuing in the 21st century at an accelerated pace. Research on the causes of this continuing decline and actions to prevent further disruption of male reproductive health are urgently needed.