Doctor warns of rise in bizarre 'winter penis' which causes organ to shrink by up to 50 per cent - here's how to avoid it

Doctors have warned British men that they may be about to suffer difficulties in the bedroom, due to a weather-related affliction known as 'winter penis'.

The phenomenon describes how male genitals shrink when the temperature drops, as a result of restricted blood flow to the area. 

Not only does this lead to a size reduction of up to 50 per cent, the reduced blood flow to the area can make it more challenging for a man to maintain an erection.

Dr Donald Grant, a GP and senior clinical advisor at The Independent Pharmacy, explained that the problem happens because the body 'prioritises blood flow to more important parts of the body' in the cold, such as internal organs.

While most men who experience 'winter penis' will find it only occurs briefly and occasionally, it can be far worse for those with underlying erectile dysfunction (ED). 

Some 4.3 million men in the UK are thought to suffer with erectile dysfunction, according to The Urology Foundation. 

'Men who already suffer from ED could find their condition more difficult to manage, when weather begins to deteriorate,' said Dr Grant.

Dr Grant said winter penis is a perfectly natural reaction the body undergoes to protect the organ from frigid weather, and can affect men of all ages. 

'Winter penis is the body's temporary response to the drop in temperatures which causes the penis and testicles to shrink in size,' he said. 

'The testicles shrink so they remain as close to the body as possible to stay warm.'

Winter penis also has a simple fix: once you warm up the size of the organ will return to normal, as body stops adapting to better survive the cold, he added.

However, experts warn that just because winter penis exists men shouldn't dismiss consistent changes to the size and function of their penis. 

Dr Grant recommended any man experiencing a longer term change in the shape of their genitals, including the testes, or the blood flow to their member to seek advice from their GP as a precaution. 

Additionally, any man suffering from ED should seek out help as range of treatments and medications can help address the problem. 

This is important because not only is sexual function a key aspect of people's wellbeing, but ED can also sometimes be an indicator of serious health problems like cardiovascular disease. 

Winter penis shouldn't be confused with frostbite, a serious medical condition where tissue is exposed to extremely cold temperatures. 

With frostbite the affected area begins to feel cold and painful as blood withdraws from the area to protect internal body temperature.

If exposure to cold continues, the sensation of pins and needles can happen before the area finally numbs over as tissue freezes, damaging it.

In extreme cases the tissue can be lost as a result, requiring amputation.

Frostbite of the penis is rare compared to other parts of the body such as the ears or fingers as the genitals are more likely to be wrapped in clothing if someone is caught outdoors. 

The NHS says those who suffer frostbite — most commonly climbers, skiers and the homeless — should be taken to warm environments urgently.