The study, released in December 2004, proposed that laptop computers can pose a long-term threat to the fertility of young men who use them by raising temperatures in the genital area that might slow or stop sperm formation.
Sources such as WebMD reported that researchers studied 29 healthy young men, 21 to 35, for two one-hour sessions in a climate-controlled room. After having their body temperatures taken and standing in the room for 15 minutes to adjust to the room's temperature, they sat down and were given working or nonworking laptop computers.
The researchers used two brands of computers, which weren't identified in the study. The men's scrotal temperature was recorded every three minutes. The temperature on the bottom of the working computers was also monitored. Scrotal temperature rose with the working and nonworking computers. However, the working laptops
produced a greater increase in scrotal temperature -- around a 5 degrees Fahrenheit increase. Participants without working laptops had a scrotal temperature increase of about 3 to 4 degrees Fahrenheit.
Some of the increase was attributed to the fact that thighs were held tightly together to balance the laptops. That can increase scrotal temperature, as well. While the researchers weren't concluding definitely that higher scrotal temperatures could cause reproductive problems, they did feel confident in concluding that putting the appropriately named "laptop" on a guy's lap can reduce sperm count. They coined a good expression for the condition: scrotal hyperthermia.
Stacey's comment:
This is one suggestion that we give men in our clinic, keep the laptops off your laps and its based on this and another study that showed a man actually burned his scrotum by keeping a lap top on his lap while it heated up. All I can say is "Ouch!"
The interesting thing also was that even in the non working laptops men's scrotal temperature increased by almost the same amount as in the working laptops.
Other things that have been shown to possibly effect motility are hot baths. However, the sperm's motility (its swimming ability) did return to its previous levels after a while. Certainly if you all ready have male fertility issues with sperm production and quality such as motility or abnormal forms of sperm, it would be good to avoid these activities all together.
