Duchess of Cambridge in 'early stages' of labour

British royal Catherine, Duchess of Cambridge is in the "early stages" of labour with her third child.

Representatives for Kensington Palace announced on Twitter on Monday morning (23Apr18) that the 36-year-old had been admitted to the Lindo Wing at St. Mary's Hospital in Paddington, London ahead of the baby's birth.

"Her Royal Highness The Duchess of Cambridge was admitted to St. Mary’s Hospital, Paddington, London earlier this morning in the early stages of labour," the statement read. "The Duchess travelled by car from Kensington Palace to the Lindo Wing at St. Mary’s Hospital with The Duke of Cambridge."

Crowd barriers and parking restrictions were put in place outside the hospital in preparation for the birth earlier this month. The Duke and Duchess of Cambridge previously used the facility for the births of their son George, four, and daughter Charlotte, two.

The new baby will be Queen Elizabeth II's sixth great-grandchild and fifth in line to the throne following its grandfather Prince Charles, father Prince William and its siblings, regardless of gender.

The royal couple announced they were expecting their third child in September (17) as Catherine had to pull out of an engagement as she was suffering from hyperemesis gravidarum, or severe morning sickness, as she did with her previous two children.

Catherine has been on maternity leave since 22 March, and was noticeably absent from the Queen's birthday concert at London's Royal Albert Hall over the weekend. Prince William still attended alongside his brother Harry and his fiancee Meghan Markle, among others.

The labour news comes shortly after it was reported that Catherine's sister Pippa is pregnant with her first child with husband James Matthews.