In the last 50 years, average sperm counts have fallen by 50 percent. This isn’t just happening in the U.S. or Europe or Asia. It seems to be happening everywhere. If the current rate of decline continues, researchers concluded, the average male sperm count will fall so low that the typical guy in every advanced economy will be infertile by 2050. Harvard's Jorge Chavarro, a professor of nutrition and epidemiology, breaks down the data on declining sperm counts and tells us what it means, what might be causing it, what men can reasonably do to avoid it, and how bad it could get.

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Host: Derek Thompson

Guest: Jorge Chavarro

Producer: Devon Manze

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