Chrissy Teigen asked her doctor if she could send him pictures of her bottom to find out if she has a "rash" on her butt.

Chrissy Teigen

Chrissy Teigen

The 31-year-old model has been left concerned by mysterious marks on her derriere, so has sent a text message to the male medical expert she regularly sees in the US to ask if she can photograph her behind and get an expert opinion about her ailment.

She wrote on Twitter: "my doctor was kind enough to give me his number and I'm gonna make him regret this (sic)"

Chrissy posted a screenshot of the messages she had written to her doctor, which read: "Can I send you a picture of my buttcheek. I think I got some sort of bites or rash from snorkeling in Italy.

"I am in London or I would come in (sic)"

While the star - who has 16-month-old daughter Luna with husband John Legend - is concerned about her butt, she also revealed she has been known to wear adult diapers.

In response to a question on Twitter about whether she wears "adult baby diapers" or has ever "thought about it", Chrissy replied: "yes and yes (sic)"

Last month, the 'Lip Sync Battle' star admitted she has cried to John in the past because she is unhappy with her appearance.

She said: "I'm in a weird phase where I'm jealous of those bodies.

"My old ass will go on social media, and I will look at the Photoshopping, Facetuning, and the apps - and everything that goes into creating what is now a hit Instagram photo - and I feel insanely inadequate.

"There have been times I've cried to [husband] John [Legend], where I felt like I would just never have 'that' body. I've definitely been really upset with ... you know, everyone has a butt now, everyone has curves, and a little waist, and that's not me."