Though I personally have yet to become a parent, I can imagine the decision to start a family is a powerfully emotional moment for any two people. So when nearly 1 in 8 couples struggles to get pregnant today, it is not surprising that experts like Dr. Ryan P. Smith of the University of Virginia are called upon for help.

Smith is a physician and researcher who specializes in male reproductive health. Researchers like him have known for years that male fertility has been on the decline since the middle of the 20th century. Doctors know some of the causes – such conditions as increased obesity and genetic disorders, for example – but these don’t fully explain the global decline in sperm counts and sperm health. Smith and others in his field have begun to suspect that exposure to human-produced toxic compounds could be a cause. He argues that while it is difficult to “definitively establish which chemicals are causing the male fertility decline, the weight of the evidence is growing” that toxic compounds in the environment are causing these problems.

Also today:

Daniel Merino

Assistant Science Editor & Co-Host of The Conversation Weekly Podcast

For decades, sperm counts and sperm health have been declining. Carol Yepes/Moment via Getty Images

Male fertility is declining – studies show that environmental toxins could be a reason

Ryan P. Smith, University of Virginia

People are exposed to toxic substances – like pesticides, chemicals in plastics and radiation – every day. A growing body of research shows that this exposure is causing a decline in male fertility.


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