The testes develop inside the abdomen and house in the scrotum in search of a cooler environment that is required for optimal sperm production or spermatogenesis. The temperature in scrotum is at least 2 degree Celsius less than that of inside the body or the core temperature.
Laptops generate heat and working on those keeping on the lap inadvertently increases the temperature in the testes. It has been seen that an increase in temperature of testes by 1 degree Celsius adversely affected spermatogenesis. As per American Urological Association one in six couples in America suffers from difficulty in conception and in most of the case male is at fault.
Use of WiFi also has adverse effect on sperm production independent of heat factor by causing DNA fragmentation.
Keeping thighs in apposition and laptop on it invariably increases the temperature at least by 2.5 Celsius.
Though more investigations are required to definitely reach to the conclusion, it is better to avoid using laptop on laps.
