12/03/2012 11:20 EST | Updated 03/11/2013 04:54 EDT

Kate Middleton Pregnant: Duke And Duchess Of Cambridge Are Expecting (PHOTOS, VIDEO)

Squee! It's finally official: Prince William and Kate Middleton — the Duke and Duchess of Cambridge — are expecting!

Clarence House announced the happy news earlier on Monday.

The statement in full:

Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting a baby.

The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall and Prince Harry and members of both families are delighted with the news.

The Duchess was admitted this afternoon to King Edward VII Hospital in Central London with Hyperemesis Gravidarum. As the pregnancy is in its very early stages, Her Royal Highness is expected to stay in hospital for several days and will require a period of rest thereafter.

Hyperemesis Gravidarum, if you're wondering, is a severe form of morning sickness. About 70 to 80 per cent of women experience some type of the condition early on in a pregnancy, but only one to two per cent suffer from this form. According to, the main difference between morning sickness and hyperemesis gravidarum is that nausea caused by morning sickness usually subsides after 12 weeks; due to her hyperemesis gravidarum, Kate's nausea could continue throughout her entire pregnancy.

ALSO: Twitter reacts with Will and Kate's baby news.

Canadian Prime Minister Stephen Harper and Gov. Gen. David Johnston both Tweeted their congratulations to Will and Kate. The prime minister passed on his best wishes and those of his wife Laureen, calling it "wonderful news."

Already, outside of Kate's hospital, hundreds of paparazzi have begun to congregate -- they no doubt hope to snap the first shot of the "Royal Baby Bump." (Though we've likely seen it growing bit by bit over the past few months.)

RELATED: Canada Set For New Law In Case Kate's Royal Baby Is A Girl

No details have been announced of where the birth will take place, but the Royal heir could be born at the same hospital as Princes William and Harry -- St Mary's, Paddington.

For Royal watchers, this is the biggest news since the Royal couple got engaged nearly two years ago. (Except for, of course, the Queen's Jubilee celebrations.)

No one really knows how long Kate has been pregnant, but we thought we'd have a little fun and play "bump watch." Take a look at the images below and let us know when you think she'll give birth. Oh, and be sure to check out our liveblog below for the latest updates.

How Long Has Kate Middleton Been Pregnant?