The Duke and Duchess of Cambridge are expecting a baby, St James's Palace announced today.

The Queen and Duke of Edinburgh, the Prince of Wales and members of both families are delighted with the news, said a spokesman.

But St James's Palace said in a statement that Kate, who is from Bucklebury, over the border in West Berkshire, had been admitted to a private hospital for treatment for a severe form of morning sickness known as hyperemesis gravidarum.

St James's Palace said in the statement: ''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.''

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