St James Palace has announced The Duke and Duchess of Cambridge are expecting their first child.
The palace said the duchess was admitted to the King Edward VII Hospital in London this afternoon with acute morning sickness.
She is expected to be in hospital for a few days.
A spokesman said: “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.”