Sperm cells are some of the most sensitive cells in the body. Not only do they need an environment free of toxins and a very specific set of vitamins- they're also incredibly sensitive to temperature. In fact, sperm are so sensitive to heat that the testicles hang outside of the body to preserve sperm from less than ideal body temperature.
Sperm thrive in lower temperatures. Ideally, they should only be exposed to 4° F below body temp (roughly 94°) or cooler. This means that even small sources of heat can start to add up and damage your sperm count.
That heat on your legs after you've worked on your laptop for a few hours has also been slowly heating up your testicles. This is a quick fix- only use your laptop on a table or desk.
Putting your phone in your front pants pocket exposes your sperm cells to the battery's heat and electromagnetic waves. While the effects of electromagnetic radiation on sperm cells is still being studied, the effects of the heat will quickly fry your sperm. Avoid this by keeping your cell phone in your back pants pocket, shirt pocket, or a separate bag.
Hot Showers/Baths, Hot tubs, or Saunas
The warmth that makes hot water and saunas so relaxing also causes your testicles to be exposed to higher temperatures for an extended amount of time. Try keeping showers and baths to 15 minutes or less, and limiting hot tub and sauna usage to less than once a week.
Most stoves and grills are typically about waist-high on men. This means they are the perfect height to deliver a direct dosage of heat to your groin. Try taking breaks while cooking, limiting time spent cooking, or getting one of these protective aprons.
While biking is a great workout and an efficient way to get around, the tight clothing associated with competitive cycling can trap heat around your testicles. Avoid tight cycling gear or take frequent breaks to cool off.
High fevers drive up your body temp, causing your own body to kill your sperm. Since fevers are mostly unavoidable there's not much to do except focus on getting better. However, the effects of your fever on your sperm count should be repaired in around 72 days, when the next batch of sperm cells fully matures.
A great way to reverse the effects of daily heat exposure is by icing your testicles. Think of it like icing any other part of your body- the same rules apply. Ensure there's a layer between your skin and the ice, and if you feel any pain, stop immediately.