Sperm counts are dropping in the Western world, but no one is quite sure why

Not all is well when it comes to men's sperm counts across the Western world.
A new, wide-reaching study published in the journal Human Reproduction Update, has found that sperm counts among men in the U.S., Europe, Australia, and New Zealand have declined by about 50 percent in the last 40 years.
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For the new research, scientists reviewed 185 studies published between 1973 and 2011. In total, these studies w