A royal pregnancy

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images
Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images
Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

A man wearing a Prince William, Duke of Cambridge mask is escorted away by a police officer from the King Edward VII Private Hospital in London, England. Photo by Chris Jackson/Getty Images

A man wearing a Prince William, Duke of Cambridge mask is escorted away by a police officer from the King Edward VII Private Hospital in London, England. Photo by Chris Jackson/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

A selection of the front pages of the UK National newspapers showing news of the Duchess of Cambridge's preganancy. Photo illustration by Dan Kitwood/Getty Images

A selection of the front pages of the UK National newspapers showing news of the Duchess of Cambridge's preganancy. Photo illustration by Dan Kitwood/Getty Images

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

Prince William Duke of Cambridge departs the King Edward VII Private Hospital in London, England. Photo by Stuart Wilson/Getty Images

The Duke and Duchess of Cambridge's Official website after it went down due to high demand when the couple announced the pregnancy of Catherine, Duchess of Cambridge. Photo by Chris Jackson/Getty Images

The Duke and Duchess of Cambridge's Official website after it went down due to high demand when the couple announced the pregnancy of Catherine, Duchess of Cambridge. Photo by Chris Jackson/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

The King Edward VII Hospital where Catherine, Duchess of Cambridge is currently undergoing care in London, England. Photo by Danny Martindale/Getty Images

An emergency trip to the King Edward VI hospital as led the Duke and Duchess of Cambridge, William and Catherine, to announce that they are expecting a child.

The Duchess, believed to be 12 weeks pregnant, is currently being treated in King Edward VII hospital with acute morning sickness.

The severity of her sickness has fuelled speculation that she may be expecting twins.