At some point in 4th grade some girl told us you couldn't get pregnant if you had sex in a Jacuzzi. Thankfully we realized that girl was an idiot. But: Dudes who hang out in hot tubs have impaired sperm function, reports the New York Times. The crazy part is that it's completely reversible: just stop the "exposure to wet heat" and the count goes back up! Except for guys who are also chronic smokers. They're screwed, so to speak. [NY Times]