Trying for a baby? Men should beware of the heated blankets and car seats this winter, fertility experts say

Freezing temperatures have made cosy heated blankets and car seats increasingly popular, but experts now warn they could harm male fertility.

It has long been known that long, hot baths are bad for men trying to start a family, as testes need to remain cool for optimal sperm production.

But electric blankets on the lap, and sitting on heated car seats, can have a similar effect over time, which may make it more difficult for men to get their partners pregnant, according to some experts.

Dr Ippokratis Sarris, a consultant in reproductive medicine and director of King’s Fertility, told the Daily Mail: ‘While heated car seats and heated blankets offer an effective and tempting way to keep warm during the cold weather, prolonged use could potentially pose risks to male fertility by increasing the temperature of the testes to levels that can affect sperm production.

‘Although this would be reversible, if someone is trying to conceive, it’s advisable to consider balancing cosiness with safeguarding their reproductive health during the colder seasons.’

It has long been known that long, hot baths are bad for men trying to start a family, as testes need to remain cool for optimal sperm production. But electric blankets on the lap, and sitting on heated car seats, can have a similar effect over time, which may make it more difficult for men to get their partners pregnant, according to some experts

Studies show a rise in temperature can change sperm count, the shape of sperm and how fast they can swim. Men who wear skintight cycling shorts have been warned about overheating their groin area, and the British Fertility Society has previously cautioned men against using a warm laptop directly on their lap

Sperm production requires the testicles to be several degrees cooler than the rest of the body, which is why they are kept cool by hanging outside of the body.

Allan Pacey, a male fertility expert who is professor of andrology at the University of Manchester, said: ‘We’ve known for a while that heating the testicles through the wearing of tight pants or sitting down too long behind the wheel of a vehicle can reduce sperm production.

‘Therefore, by logical extension, I would imagine that the use of heated car seats or electric blankets during this cold snap might do the same thing.

‘My advice to any men planning to try for a pregnancy with their partner is to keep their heated car seats and electric blankets turned off. It could make all the difference.’

Studies show a rise in temperature can change sperm count, the shape of sperm and how fast they can swim.

Men who wear skintight cycling shorts have been warned about overheating their groin area, and the British Fertility Society has previously cautioned men against using a warm laptop directly on their lap.

Dr Channa Jayasena, head of andrology at Imperial College London, said: ‘Anything that heats up the testes can damage some of the sperm, which makes them less likely to fertilise an egg.

‘The worst culprits are long cycle rides in lycra or long, hot baths. Occasional use of heated car seats and electric blankets should not be a problem.’

But he added: ‘It remains to be proven, but prolonged and regular use of heated car seats and electric blankets might be bad for a man’s fertility.’

Terry Sullivan, managing director of Fertility Family, a firm selling supplements claimed to boost fertility, said: ‘Even small temperature increases can inhibit the production of sperm.

‘Prolonged exposure to heat, whether from heated blankets, saunas, or heated seats, has the potential to adversely affect male fertility.’