The Duke and Duchess of Cambridge's baby is due in July. The announcement has come from St James's Palace.
A spokesman also said that Kate's condition is continuing to improve afte her stay in hospital for severe morning sickness. The Duchess, who was born in Berkshire, is believed to be around 13 to 14 weeks pregnant.
A St James's Palace spokesman said:
"Their Royal Highnesses the Duke and Duchess of Cambridge are delighted to confirm they are expecting a baby in July," said a St James's Palace spokesman.
"The Duchess's condition continues to improve since her stay in hospital last month."