The sperm count of men in the western world has fallen by more than half over a period of 40 years, according to an international study described by its authors as “an urgent wake-up call” about declining male health.
“Decreasing sperm count has been of great concern since it was first reported 25 years ago,” said senior author Shanna Swan of Icahn School of Medicine at Mount Sinai, New York. “This definitive study shows . . . that the decline is strong and continuing.”
The researchers, led by Hagai Levine of Hebrew University of Jerusalem, screened 7,500 sperm studies carried out worldwide between 1973 and 2011. They chose for meta-analysis 185 studies that met high standards of design and laboratory practice.
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