Should you wear pants under PJs or knicks under nighties? Holly Willoughby doesn’t...

Watch: Holly Willoughby admits she doesn’t wear pants to bed

Holly Willoughby couldn't stop laughing as she was forced to admit live on TV that she doesn't wear knickers to bed.

On yesterday's 'This Morning' show, during a debate over whether or not you should wear underwear under pyjamas, Phillip Schofield had been grilling his co-host on her own bedtime routine.

"Susannah Constantine has discussed whether it's acceptable to wear pants under pyjamas in bed - this was on her podcast, My Wardrobe Malfunction," Willoughby explained.

"Susannah said that she sometimes did, but Emma Barnett, who hosted BBC Women's Hour, was resolute that knickers should always be worn under PJs, but listeners did not agree."

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After the other guests discussed what they wore in bed, Schofield remarked: "Holly, you started this! We've all 'fessed up. Do you wear pants under you pyjamas?"

Willoughby sheepishly started to say: "Well, I would wear a big T-shirt..."

Aware that she wasn't answering the question, Schofield pushed: "Yes, but would you wear pants under your pyjamas?"

Giving in to the interrogation, the presenter eventually admitted: "No pants, no pants, no pants."

The revelation came following a divisive debate on Twitter when Barnett asked her followers whether or not they go pant-less in bed.

"How is this a debate? Of course knickers under pyjamas," she wrote. "Where do you stand?"

And social media was divided over the conundrum: "No to pyjamas in bed. Wear a nightdress and let your bits breathe!" one wrote.

"Def no knickers. Why would you wear knickers to bed?" another disagreed.

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To commando or commandon’t – that is the question, but what do the experts say about wearing underwear to bed?

"Following Holly Willoughby's revelation that she doesn't wear underwear in bed, social media is abuzz with debate on the topic," says Stephanie Taylor, intimate health expert and managing director of Kegel8.

"However, there's really nothing weird about it. In fact a 2017 YouGov survey found that 69% of Brits, particularly young women, were wearing knickers under their pyjamas."

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Interestingly, for some women the wearing of underwear at night can actually be beneficial.

“For those that suffer a flare-up of vulvo-vaginal symptoms at night, such as itching, wearing underwear can sometimes provide protection to the skin," explains Julie Bowring, consultant gynaecologist at London Gynaecology.

But for other women Taylor says wearing pants under your PJs could be damaging to your vaginal health.

"Underwear is a breeding ground for bacteria, due to the moisture-collecting fabric being tight to the vagina," she explains.

"Our intimate area needs space to breathe, so having time in the day without pants is important."

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If you are particularly prone to vaginal infections Taylor says it’s probably a good idea to avoid wearing underwear to bed since this reduces the amount of time genitalia is exposed to bacteria and minimises moisture build-up.

"When we sleep it is particularly important, as our body temperatures tend to fluctuate, which can lead to sweating.

"While perspiration is perfectly natural, when we're sleeping we spend hours without getting up to walk around, meaning our pants don’t ‘air’ and the sweat sits stagnant, which could lead to uncomfortable common infections – thrush, bacterial vaginosis and so on."

If you're not ready to ditch your knicks just yet, however, Taylor suggests using your time at home in the evening as a pant-free period for your vagina.

And if you really can't bear the thought of parting with your pants in the sack, she recommends turning to looser-fitting alternatives.

"This means no unbreathable material like lace or satin and definitely no thongs," she adds."Crack out your big cotton ‘granny pants’ or briefs and let your intimate area have some much needed airtime."

Bowring adds that some clothes dyes and synthetic materials have been linked to causing dermatitis and itching, so it’s always preferable to choose non dyed cotton underwear.

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