Speedy labour expected for Duchess's third baby
The Duchess of Cambridge's third labour is expected to be fast - if not faster - than before.
Although it varies from woman to woman, some mothers report a speedier delivery third time around.
For first-time mothers, active labour may take around eight hours and in a second labour around five hours, according to Babycentre.co.uk.
When Kate gave birth for a second time, she delivered Princess Charlotte just two hours and 34 minutes after being admitted to hospital.
With Prince George in 2013, the duchess went into hospital at around 6am and her son arrived 10-and-a-half hours later at 4.24pm.
Clare Livingstone, professional policy adviser at the Royal College of Midwives, said: "It will vary from one woman to another. Some women report a quicker labour with their third baby but not everyone.
"It seems to be though that they do go more quickly. It's a very individual thing."
It is not known how long the Duchess was in labour with George and Charlotte before she was admitted.
Mrs Livingstone added that quick labours can appear more painful.
"The body has natural painkillers - endorphins - which build up over a period of time. So a quick labour doesn't allow the body the opportunity to do that," she said.
Advice site Madeformums.com said 2% of women experience a precipitate labour - where labour is extremely rapid and lasts less than two hours from first contraction twinge to giving birth.
"They're more common among women who've already given birth at least once," the site said.
Kate had a straightforward, natural birth with George and Charlotte with no complications.