Men might improve their fertility by reducing how much pollution they breathe in. The dirtier the air, the lower a man's sperm count and the more sperm with fragmented DNA he produces, two new studies suggest.
However, neither report directly links the decline in sperm quality to fertility problems.
"The decrease is not enormous," comments environmental chemist Brian McCarry of McMaster University in Hamilton, Ontario, who was not involved in either study. "There's no evidence that it has an impact on fertility."