If you are a male reader & presently reading this post by placing the laptop below your waist lying down then your scrotum can be in danger.
image courtesy: fourwallsnolimits.net
This effect is not due to the placement of laptop over scrotum but due to the position of legs in which the person lies down and uses laptop..
A study just published online in the journal Fertility and Sterility investigated ways to avoid the testicles from overheating while using a laptop computer.
Right and left scrotal temperature were measured in 29 volunteers while working on the laptop in different positions: with closely approximated legs; with closely approximated legs with a lap pad below the laptop; and sitting with legs apart at a 70° angle with a lap pad below the laptop.
After 60 minutes, with closed legs, temperature increased about 2.4 degrees Celsius, using the lap pad yielded a slightly smaller increase of 2.1 degrees, while spreading the legs resulted in a modest increase of 1.4 degrees.
The authors conclude that prevention of scrotal hyperthermia in laptop users is not feasible, although we would like to disagree and suggest using a flat surface, such as a table or desk, to position your laptop in order to preserve your fertility.
- Laptop Use Causes Scrotal Hyperthermia (medgadget.com)