Sperm parameters can be affected if exposed to high temperatures.

For instance, sitting in a hot tub day after day should be avoided, even if a man has no known fertility problems. Repeated exposure to high temperature through hot tubs or hot baths can affect male fertility.

Extremely tight clothing, long periods of cycling can also have an impact on sperm quality.

Scrotal temperatures can rise in laptop users who place the computer on their laps.

Heat created from laptops can have affect male fertility:
Laptop