Clarence House has confirmed that Catherine, the Duchess of Cambridge, has gone into labor with her first child with Prince William.
The couple are believed not to know the gender of their baby and have planned a natural birth. The palace will not confirm whether or not Kate was induced, but given that she arrived by car "in the early stages of labor," it seems unlikely. The Duchess will have her baby in the same wing of the private London hospital where her husband was born 31 years ago.
The royal baby will be third in line to the throne and be called "His/Her Royal Highness, Prince or Princess [Name] of Cambridge." As soon as the baby is born, Prince William will begin two weeks of paternity leave from the Royal Air Force.
The next public announcement will be made in the form of a formal bulletin signed by medical staff and driven from the hospital to Buckingham Palace, where it will be displayed on an easel in front of the palace. The bulletin will reveal the baby's sex, weight, and time of birth, but it may take William and Kate longer to decide on a name — Prince William's name was announced six days after his birth and it took the world nearly a month to learn Prince Charles' name.
The news broke after a photographer spotted the security convoy pulling up to one of the hospital's private entrances.
The impending birth is welcome news to the members of the media who have been camped outside the hospital since July 1.
Update: 3:35 a.m. ET: A spokesman for the Duchess says that Kate's labor is "progressing naturally."
The palace has previously indicated that they will be making no further statements on the progress of the birth until the child is born.
Security has increased outside St. Mary's private Lindo Wing.
St Mary's released a brief statement regarding the news:
The hospital is delighted that the Duke and Duchess of Cambridge have chosen to have their baby at the Lindo Wing at St Mary's.
Everyone at the trust is exceptionally proud that this historic moment is happening here.
The media presence outside the hospital has increased since the announcement.
Many royal fans have arrived on the scene as well, and barricades have been put in place to keep the road clear.
Update - 6:20 a.m. ET: UK Prime Minister David Cameron and the Archbishop of Canterbury have sent their well wishes to the expecting couple.
The Prime Minister told ITV that the news that the Duchess of Cambridge had gone into labor was "very exciting" for the entire country. "Best wishes to them," Cameron said. "A very exciting occasion and the whole country is excited with them. So, everyone's hoping for the best."
Update - 6:45 a.m. ET: A live stream has been set up outside the hospital doors.
Prince Charles gave a short comment to reporters while at an event in Yorkshire:
Update - 7:45 a.m. ET: Crowds are beginning to gather outside Buckingham Palace.
Update - 9:10 a.m. ET: A spokesman for the royal couple has confirmed that the Duchess of Cambridge's labor is "progressing as normal."
Update - 10:45 a.m. ET: The Queen has returned to Buckingham Palace to await the birth of her third great-grandchild.
Update - 11:35 a.m. ET: Prince Charles thanked well-wishers and quipped about the duration of his daughter-in-law's labor.
Update - 1:00 p.m. ET: The BBC's Peter Hunt explains how the world will learn of the royal baby's birth.
Update - 1:25 p.m.: In York today, a little boy gave Prince Charles a gift, "for the baby." The prince thanked him and said, "I'll see what I can do, it hasn't quite appeared yet."
Update - 3:05 p.m. ET: The baby's birth announcement will break from tradition and come via press release instead of a posted notice at Buckingham Palace.
Update - 3:30 p.m. ET: Reporters outside the hospital believe the birth announcement is coming soon.
Update 3:30 p.m. ET: Clarence House confirms Kate gave birth to a baby boy.
Michael Rusch is a socials editor for BuzzFeed News and is based in New York. Rusch was selected by Time as having one of the 140 Best Twitter Feeds of 2013.
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Ellie Hall is a reporter for BuzzFeed News and is based in Washington, DC.
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