© Getty Images

Queen Elizabeth II -

The then-Princess Elizabeth was four-months pregnant with her first son, Prince Charles, when this picture was taken, in 1948.

© Getty Images

Queen Elizabeth II -

This photo was taken in January 1960, when the Queen was expecting the birth of her son Prince Andrew. Queen Elizabeth II had two more children: Princess Anne and Prince Edward.

© Getty Images

Princess Margaret, Countess of Snowdon -

Princess Margaret is pictured in March 1964, pregnant with her daughter, Lady Sarah Chatto. This was her second child, following David Armstrong-Jones.

© Getty Images

Princess Anne -

Princess Anne was expecting her first child, Peter Phillips, in 1977.

© Getty Images

Princess Anne -

Three years later, in 1981, Princess Anne gave birth to her daughter, Zara Tindall.

© Getty Images

Diana, Princess of Wales -

Lady Di and Prince Charles had two sons, Prince William and Prince Harry.

© Getty Images

Diana, Princess of Wales -

Diana's first son, William, was born in 1982 (this picture was taken just two weeks before his birth) and Harry in 1984.

© Getty Images

Diana, Princess of Wales -

Lady Di is pictured wearing a Bellville Sassoon maternity coat in 1982, in Huddersfield, England.

© Getty Images

Diana, Princess of Wales -

In this picture, taken in 1984, the Princess of Wales was expecting her second child, Prince Harry.

© Getty Images

Sarah, Duchess of York -

Sarah Ferguson and Prince Andrew, Duke of York, have two children together: Princess Beatrice and Princess Eugenie.

© Getty Images

Sarah, Duchess of York -

This photo was taken in July 1988, when the Duchess of York was heavily pregnant with Princess Beatrice.

© Getty Images

Sarah, Duchess of York -

And in this photo, Sarah Ferguson was pregnant with her second daughter, Princess Eugenie, in 1990.

© Getty Images

Sophie, Countess of Wessex -

The Countess of Wessex and her husband, Prince Edward, have two children together: Lady Louise Windsor and James, Viscount Severn. In this picture, taken in 2003, Sophie was pregnant with her daughter, Louise.

© Getty Images

Catherine, Princess of Wales -

The Duchess of Cambridge has had three children so far: Prince George, Princess Charlotte, and Prince Louis.

© Getty Images

Catherine, Princess of Wales -

Kate Middleton's children were born in 2013, 2015, and 2018, respectively.

© Getty Images

Catherine, Princess of Wales -

Here, Kate Middleton attends a Garden Party hosted by the Queen in Buckingham Palace, on May 22, 2013.

© Getty Images

Catherine, Princess of Wales -

The Princess is pictured leaving the Royal Society of Medicine on March 21, 2018 in London, England.

© Getty Images

Meghan, Duchess of Sussex -

The Duchess of Sussex is the proud mom of two children with Prince Harry: Archie and Lilibet.

© Getty Images

Meghan, Duchess of Sussex -

Archie Harrison Mountbatten-Windsor was born in 2019, and Lilibet Diana Mountbatten-Windsor was born in June 2021.

© Getty Images

Meghan, Duchess of Sussex -

The couple attends a reception hosted by the British Ambassador to Morocco at the British Residence on February 24, 2019 in Rabat, Morocco.

© Getty Images

Meghan, Duchess of Sussex -

Markle is pictured arriving at animal welfare charity Mayhew on January 16, 2019 in London.

© Getty Images

Zara Tindall -

The daughter of Princess Anne has three children in total: Mia Grace Tindall, Lucas Tindall, and Lena Elizabeth Tindall.

© Getty Images

Queen Máxima of the Netherlands -

The then-Crown Princess Maxima, pregnant with her third child, Princess Ariane, in 2007.

© Getty Images

Queen Máxima of the Netherlands -

Queen Máxima of the Netherlands has three children in total: Princess Catharina-Amalia, Princess Alexia, and Princess Ariane. In this picture, taken in 2003, the then-Princess Máxima was pregnant with her first daughter.

© Getty Images

Mette-Marit, Crown Princess of Norway -

In this photo, Princess Mette-Marit of Norway was expecting her third child, Prince Sverre Magnus, in 2005.

© Getty Images

Mette-Marit, Crown Princess of Norway -

She's also the proud mother of Marius Borg Høiby, and Princess Ingrid Alexandra of Norway.

© Getty Images

Caroline, Princess of Hanover -

The Princess was expecting her daughter Charlotte Casiraghi in this picture, taken in 1986. Caroline of Monaco has three more children: Pierre Casiraghi, Andrea Casiraghi, and Princess Alexandra of Hanover.

© Getty Images

Queen Letizia of Spain -

The then-Princess Letizia was expecting Infanta Sofía of Spain, in 2007. The Spanish Queen also has another daughter, Leonor, Princess of Asturias,  born in 2005.

© Getty Images

Queen Mathilde of Belgium -

In 2005, the then-Princess Mathilde was pregnant with Prince Emmanuel. The Belgian Queen has three more children: Prince Gabriel, Princess Elisabeth, and Princess Eléonore.

© Getty Images

Queen Rania of Jordan -

Rania Al-Abdullah, the queen consort of Jordan, has four children, born between 1994 and 2005: Crown Prince Hussein, Princess Iman, Princess Salma, and Prince Hashem.

See also: Royal babies: the bizarre traditions behind palace doors

© Getty Images