Ask the Doc: Do laptops and phones affect male fertility?

In theory, laptops and mobile phones could cause problems for male fertility because both are sources of radiation. Not the kind of radiation that you get from nuclear bombs but radiation in the form of radio waves and, for laptops, also heat.

There’s no doubt that radiofrequency electromagnetic radiation (the transfer of energy by radio waves) and heat can both damage sperm — that’s been demonstrated convincingly by lots of experimental studies¹. But good evidence of impaired fertility in men, from normal use of phones and laptops, just doesn’t exist.

There’s a study of the effects of laptops, that was performed 20 years ago, that’s mentioned in a few articles online. Researchers measured the temperature of the scrotums of 29 men, who sat for one hour either without a laptop on their lap or with a laptop that was turned on².

The men’s scrotal temperatures increased while they sat but there wasn’t a huge difference between when they had a laptop on their lap and when they didn’t. The increase was between 1°C and 5.1°C with the laptop and between 0°C and 4.5°C without, and just sitting accounted for around 75-80% of the increase in scrotal temperature.

What the research doesn’t tell us is what happens to the temperature of the testes, where the sperm are being made, and it doesn’t tell us whether a temperature change like this affects the sperm.

Another recent study looked at a bunch of real-world behaviours that might overheat men’s testes, and whether their partners got pregnant³. Hot baths made pregnancy less likely but laptop use had no effect.

A recent look at the scientific evidence for an effect of mobile phones on sperm, which examined the findings from laboratory experiments and studies of people, “did not support an association of mobile phone use and a decline in sperm quality” in humans⁴.

It’s a good idea to avoid anything that could damage your sperm, especially if you’re trying to have children. For people who can’t avoid laptops and mobile phones, there’s no need to be worried, especially if you’re eating well, exercising and doing other things to look after your health.