https://academic.oup.com/humupd/article/doi/10.1093/humupd/dmx022/4035689/Temporal-trends-in-sperm-count-a-systematic-reviewTemporal trends in sperm count: a systematic review and meta-regression analysis
( details )KEY FINDINGS
In this first systematic review and meta-regression analysis of temporal trends in sperm counts we report a significant overall decline in both SC and TSC in samples collected between 1973 and 2011. Declines were significant only in studies from North America, Europe, Australia (and New Zealand), where they were most pronounced among men unselected by fertility. In this latter group, SC declined 52.4% (−1.4% per year) and TSC 59.3% (−1.6% per year) over the study period.
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