AS scientists learn more about the novel coronavirus (COVID-19), we are beginning to understand more of how it affects different aspects of our daily lives, both now and in the long term. One key area of concern is whether the highly contagious illness has any significant impact on our ability to reproduce.

So far, scientists agree that COVID-19 may temporarily impact fertility in men who contract the virus. As the Hugh Wynter Fertility Management Unit at The University Hospital of the West Indies explained in a series of posts on Twitter, it is not so much the virus itself that affects male fertility, but the high fever that usually accompanies it.

“Considering that one of the primary symptoms of COVID-19 is a high fever, it is reasonable to assume that men infected with coronavirus will also experience reduced fertility,” the unit said. “Seasonal flus are known to reduce male fertility, possibly due to the fever associated with the virus, which overheats the testicles.”

It was quick to point out, though, that research suggests so far that these effects are not long term.

“Studies reassure that these effects are only temporary and completely reversible,” it said.

But what does a fever have to do with your sperm anyway?

“Elevated temperatures impair sperm production and function,” The Mayo Clinic explains.

Sperm quantity (count), motility (movement) and morphology (shape) are all affected by high temperatures.

“If the motility or function of your sperm is abnormal, the sperm may not be able to reach or penetrate your partner’s egg,” it says.

You will notice that testicles hang more loosely outside of the body when you are hot, and are pulled closer to the body when you feel cold. This mechanism is used to regulate the temperature in the testicles for optimal sperm production.

But a fever is not the only thing that can increase testicular temperature and affect sperm production.

“Sitting for long periods, wearing tight clothing, or working on a laptop computer for long stretches of time also may increase the temperature in your scrotum and may slightly reduce sperm production,” the Mayo Clinic adds.

While COVID-19 does not immediately seem to have lasting effects on fertility, experts warn that it is safest to avoid contracting the virus altogether, because it is yet to be fully understood. It may very well have no effect, but the possibility of long-term effects is all the more reason to stay home as much as possible, wash your hands, and try to keep the boys cool.