Gentlemen, Start Your Engines...

Because it turns out that biological clocks aren't just for the ladies. New evidence points to a decline in fertility when men reach their mid-30s. Researchers in France tracked more than 12,000 couples under treatment for infertility over a period of five years. They found that women's chances of getting pregnant dropped after they hit 35, but that was expected. More surprising was the finding that men lost some of their baby-spawning mojo around the same time. This is becoming a theme.