Heatwaves can have a devastating impact on a man's sperm count.
Heatwaves destroy a man's sperm count
A study in Singapore has found that the swimmers are affected if temperatures rise above 30C and has raised concerns about the impact of climate change on fertility.
Dr. Samuel Gunther, from the Yong Loo Lin School of Medicine, said that the reproductive cells of males aged between 25 and 35 were most at risk in the extreme heat.
He said: "Conventionally, findings suggest that sperm quality decreases as one ages, but what we found in this study was that it was men in their (prime) reproductive time between 25 and 35 who were the most impacted by heat.
"So just because you're a young male, don't think you're invincible and don't think you're not also vulnerable to these impacts.
"Moving forward, the climate is going to get hotter. That is also something that we need to bear in mind in family planning."