Here is a summary of some research undertaken to find out the impact of testosterone levels with laptop use: In a one-hour study, 29 healthy males aged 21-35 had their scrotal temperature taken every three minutes, whilst balancing working and non-working laptops on their laps. The study concluded that the scrotal temperature rise increase was greater with working laptops; around 5 degrees Fahrenheit/2.7 degrees Celsius. Those without working laptops had a scrotal temperature increase of about 3-4 degrees Fahrenheit/2.1 degrees Celsius. Balancing the laptop on closed thighs also increases scrotal temperature, however, the heat generated by the laptops adds to the problem.