Why is Male Fertility Declining?

You may not know this, but male fertility has been experiencing a bit of a worrying slump in recent years.

Various studies have found sperm counts in decline with an important 2013 study of French men finding sperm concentrations dropped by nearly 2% each year from 1996 to 2005. ?In further alarming news, rates of testicular cancer and genital birth defects are on the rise.

Newsweek reports scientists researching these male reproductive problems are blaming endocrine-disrupting chemicals for the increase in reported cases and the steady decline in sperm counts. Niels Skakkebaek, a Danish researcher as the University of Copenhagen, told the publication, ?There is little doubt that factors in our environment have adverse effects on human testicles.?

And now the scientific journal PLOS Genetics has published a paper pointing to the endocrine-disruptor bisphenol A (BPA) as one of the most likely reasons for this decline of male fertility. BPA is found in many materials with which humans come into contact on a daily basis, including plastics and receipts. It mimics the effects of the predominantly female hormone estrogen, over-exposure to which researchers claim negatively affects human physiology.

This study exposed mice - not humans, so the effects on actual men have yet to be proven - at birth to different levels of BPA concentrations for short periods. By the time the mice were sexually mature their sperm count was significantly lower in two out of three cases. The only strain of mice not affected by BPA was the inbred kind.


To see if there was any way to reverse this lowering of sperm count, scientists transplanted mice with stem cells, but there was no change from before. This is yet more bad news, as it suggests BPA exposure leads to a permanently-lowered sperm count.

Pretty scary findings. So we guess its organic everything if you're hoping to become a father?

Follow Jeanne Sutton on Twitter @jeannedesutun

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