Chrissy Teigen sends her husband John Legend ''super sexy photographs'' to spice up their marriage.

The 31-year-old model may have allowed her mother Vilailuck to move in to their home, but she's adamant her relationship hasn't suffered as a result because she knows how to keep the 'All of Me' hitmaker, with whom she has 18-month-old daughter Luna, on his toes and ensure he only has eyes for her.

Speaking during Vogue's 73 Questions, she said when asked her secret to her four-year marriage: ''Keeping things sexy by taking super sexy photos.''

But it's not just her husband Chrissy sends explicit photos to, as she once asked her doctor in the US if she could send him pictures of her behind to find out if she has a ''rash'' on her butt while she was in London.

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

She then 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)''

Although she clearly has no issues stripping off and flashing the flesh, the 'Lip Sync Battle' star recently admitted she has cried to John, 38, in the past because she is so 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.''