Kate Middleton is planning on listening to Calvin Harris, Bruno Mars and Of Monsters and Men during labour.

According to the US version of OK! magazine, the Duchess of Cambridge has been filling her iPod with music to have on while she is giving birth at the St Mary's Hospital in London.

The magazine says Kate has been going "stir crazy" and has been distracting herself with music.

A source told the publication: "Kate says she's never been so nervous and feels physically sick about giving birth. To make matters worse, Prince William is still working and isn't around to comfort her. She's a real mess.

"He's expecting a phone call and a frantic dash from work when Kate goes into labour. He knows Kate's having a tough time right now and hates not being there to support her.

"She's on her own, surrounded by servants. She's going a bit stir-crazy sitting around. She has been filling her iPod with music she wants playing while she's in labour. The other day she downloaded some of Bruno Mars, Calvin Harris and Of Monsters and Men."

Kate's concern that Prince William will miss the birth of their first born was also highlighted by another insider, who told Now magazine his duties as an RAF pilot in Anglesey might prevent him from getting there on time.

Champagne on ice

"Kate's worried he might not be around," the source said. "She's feeling self-conscious because it's uncharted territory for both of them.

"It's an exciting and nervous time, but she knows that he'll do everything in his power not to let her down."

It is thought William will either be flown to the hospital by helicopter or driven to London from his post when Kate goes into labour.

The Duchess is believed to be planning a hypno-birth, which uses hypnotherapy techniques to reduce the pain and length of labour.

While Kate may be feeling nervous about the birth, other members of the royal family are looking forward to the new arrival. A source said: "Everyone is very excited. Prince Harry says he's already got the champagne on ice!

"Kate and Will can't believe the baby's almost here - in a few weeks their lives will change forever."