The Duchess of Cambridge went into labor with her third child on Monday, the office at the royal residence Kensington Palace has confirmed.

Kate Middleton and her husband Prince William travelled to hospital in London early on Monday morning, where she is being attended to by the same team of doctors that delivered

Prince George in July 2013 and Princess Charlotte in May 2015.

“Her Royal Highness The Duchess of Cambridge was admitted to St. Mary’s Hospital, Paddington, London earlier this morning in the early stages of labor,” an announcement from Kensington Palace read. “The Duchess traveled by car from Kensington Palace to the Lindo Wing at St. Mary’s Hospital with The Duke of Cambridge.”

The couple announced the pregnancy in September last year when they confirmed the baby was due in April. The sex of the baby is not known to the couple. The child will be fifth in line to the British throne, behind Prince Charles, Prince William, Prince George and Princess Charlotte.