Giovanna Fletcher admits she didn't sleep the night before interviewing the Duchess of Cambridge

Giovanna Fletcher, 35, has revealed she didn’t get any sleep before interviewing the Duchess of Cambridge on her podcast, but was eased into their conversation by remembering she was “just talking to another mum”.

Fletcher, an author and the wife of McFly’s Tom Fletcher, had Kate on her Happy Mum, Happy Baby podcast, where the royal talked about her work on Early Years. In particular, her 5 Big Questions poll.

The duchess revealed she had tried hypno-birthing and spoke about the terrifying moment she had to exit the Lindo Wing with baby George to greet the media.

Read more: Duchess of Cambridge gives 5 Big Questions survey final push in rare video

Catherine joined her on the Happy Mum, Happy Baby podcast to talk about her survey.

Speaking to guest host Christine Lampard on Lorraine on Thursday, Fletcher said Kate had been on her “wish list of guests.”

“The week before, I literally wasn’t sleeping,” she shared. “Because she’d been on my wish list for so long, and my dream guest, it’s one thing to actually want someone on and then to get them and go ‘Oh my gosh, that comes with so much responsibility.’

“But as soon as I started planning out the episode and what I do every time is I map it out, write loads of questions and then I don’t look at the paper at all and just enjoy the chat, just kind of get lost in it.

“But as soon as I started remembering that I was just talking to another mum, everything else sort of made sense.”

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Giovanna Fletcher, with her husband Tom, is a best-selling author. (Getty Images)

The mother-of-three added: “That’s what the podcast’s all about. It doesn’t matter who you are, what you have, what you do - there are so many parts of motherhood that we can all relate to, and it’s a complete leveller.

“We were talking about lack of sleep - literally,  it just gets you, it takes over…

“To have her on… and it’s a brilliant time for her, the amount of work she’s done in Early Years, and that’s the amazing thing about the podcast, is you really understand how passionate she is and how much she cares for the Early Years. She’s really wanting to listen to people and what they think.”

Kate’s survey, 5 Big Questions, is the biggest of its kind and has been run with Ipsos MORI.

Read more: Who are the Queen's grandchildren?

It’s open until 21 February, and the Royal Foundation will be releasing the details of the results in the spring.

In a rare video issued on the Kensington Royal Instagram, the duchess, 38, says: “Parents, families and carers are at the heart of raising the next generation and that’s why I felt so passionate about listening to them and listening to your thoughts and your views and how best we can support you going forward.

“That’s why I’ve launched the #5BigQuestions, to hear from as many people from society as possible.”

It came even though the Duke and Duchess of Cambridge were off for half term with their three children, and weren’t taking part in any official engagements.