Argentinian scientists say they've uncovered a link between Wifi use and sperm damage - and it's got nothing to do with the videos you're watching.
Writing in Fertility and Sterility, the team from Nascentis Medicina Reproductiva in Cordoba say that Wifi can increase DNA damage and make the little chaps less mobile.
"Our data suggest that the use of a laptop computer wirelessly connected to the internet and positioned near the male reproductive organs may decrease human sperm quality," they say.
"At present we do not know whether this effect is induced by all laptop computers connected by Wifi to the internet, or what use conditions heighten this effect."
The team took semen samples from 29 healthy men and placed them under a laptop downloading data from the internet. They compared the results with those from samples stored at the same temperature away from the computer.
And, after four hours, they found that the samples exposed to Wifi showed three times as much DNA damage as the others. And only three-quarters of the sperm were still perky and wriggling, compared with 86 percent for the samples stored away from the computer.
The team blames the Wifi radiation for the effects. It's not the laptop itself, they say, as that emits negligible radiation.
Previous studies have linked laptop use with sperm damage, but the culprit was identified as temperature - sitting with one's legs apart and letting it all hang out appeared to prevent the problem.
This study is the first to link Wifi itself with sperm damage, although similar effects have been reported from the use of mobile phones.