Now that the Duchess of Cambridge is in labour, the wait is on for the official announcement of the royal baby’s birth.

Just like with Prince George and Princess Charlotte, news of the arrival of a new prince or princess will be emailed to the press by Kensington Palace, coinciding with confirmation of the birth via Twitter by @KensingtonRoyal.

Easter service at Windsor
William and Kate will want to tell the Queen before the announcement is made (Simon Dawson/PA)

William and Kate will want to inform the Queen and their families first before sharing the news with the world, so any announcement is unlikely to be made overnight.

The statement traditionally takes the form of saying the Duchess has been “safely delivered” of a son or a daughter, stating the time of birth and the weight of the baby.

It also usually reveals whether William was present at Kate’s side, which he is due to be, whether mother and baby are doing well, and how the news has been shared with delighted family members.

The arrival of the Cambridges’ third child will also be marked with a traditional bulletin on show at Buckingham Palace.

Just as when George and Charlotte were born, the age-old custom of placing a paper proclamation for the public to see at the Queen’s London residence will be carried out.

A press secretary and a footman place an easel on the forecourt of Buckingham Palace to announce the birth of Prince George in 2013 (John Stillwell/PA)
A press secretary and a footman place an easel on the forecourt of Buckingham Palace to announce the birth of Prince George in 2013 (John Stillwell/PA)

A brief formal announcement – on foolscap-sized paper set in a dark wooden frame – will be placed on an ornate golden easel on the forecourt of the Palace.

It used to be hand-written, but is now typed.

It will also be signed at the hospital by the doctors who tended to the duchess, and then ferried back to the Palace by car.

The bulletin which was hung outside Buckingham Palace in February 1960 announcing the birth of a son - Prince Andrew - to the Queen (PA)
The bulletin which was hung outside Buckingham Palace in February 1960 announcing the birth of a son – Prince Andrew – to the Queen (PA)
Policemen put up a bulletin signed by royal doctors on the gates of Buckingham Palace after the birth of Princess Anne’s first child in 1977 (PA)
Policemen put up a bulletin signed by royal doctors on the gates of Buckingham Palace after the birth of Princess Anne’s first child in 1977 (PA)

The names given to royal babies are not usually revealed straight away, and the public is often left guessing for several days.

William and Kate took two days to announce both George and Charlotte’s names, informing the Queen of their choice beforehand.

Mike and Zara Tindall used Twitter to unveil their daughter’s name six days after she was born in 2014, with the proud father tweeting: “For everyone who has asked what our daughter’s name is, it’s Mia Grace Tindall.”

When Princess Beatrice was born in 1988, it was two weeks before her name was known.

In 1982, the Prince and Princess of Wales waited seven days before deciding upon and announcing Prince William’s name.

Prince William's debut outside the Lindo Wing with his parents the Prince and Princess of Wales (PA)
Prince William’s debut outside the Lindo Wing with his parents, the Prince and Princess of Wales (PA)

The Prince of Wales’s name, however, remained a mystery for an entire month and was only declared ahead of his christening in the Music Room of Buckingham Palace in December 1948.

The birth will be celebrated with a 41-gun salute in Green Park or Hyde Park – and a 62-gun salute at the Tower of London.

The King’s Troop Royal Horse Artillery firing a gun salute to welcome the birth of Prince George in 2013 (PA)
The King’s Troop Royal Horse Artillery firing a gun salute to welcome the birth of Prince George in 2013 (PA)

Royal births are registered in the normal way, although the Home Secretary is required to notify certain officials including the Lord Mayor of London, the Governors of Northern Ireland, the Channel Islands and the Isle of Man.

The Queen’s top aide, her private secretary, Edward Young, informs Governor Generals overseas, while announcements are also made on the monarchy’s website and Facebook page.