Prince William arrived with his wife at St Mary's Hospital in Paddington, where the couple have a private suite in the Lindo Wing.
The pair arrived at the hospital without a police escort having spent the weekend at Kensington Palace.
An official statement from Clarence House read 'The Duchess of Cambridge has been admitted this morning to St. Mary’s Hospital, Paddington, London in the early stages of labour,'
'The Duchess travelled by car from Kensington Palace to the Lindo Wing with The Duke of Cambridge'.
The couple announced they were expecting their first child on December 3rd, though it is understood they did so before the 12-week mark due to concerns about Kate’s health which meant an admission and short stay in hospital.
The Queen’s surgeon-gynacologist, Marcus Setchell, is the doctor in charge of delivering of the new heir. He has been involved in the care of Kate since the announcement of her pregnancy and during treatment for hyperemesis gravidarum.
The child will be third in line to the throne, after Prince Charles and Prince William.
As news of the labour broke, Closer readers took to our Facebook page to offer good wishes and advice to Kate on enduring her first labour.
While the Duchess is said to want to deliver naturally, a large proportion of our Facebook followers encouraged the use of every drug on offer.
Andrea wrote 'drugs, drugs and more drugs' while Claire adviced 'have every single drug available and as much of it as you can'.
Others advised Kate to soak in the moment as much as possible and to concentrate on the end result, a baby that the whole world is excited to meet!
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