Australian Casey Dellacqua has announced she is pregnant with her and partner Amanda Judd's third child. The 33-year-old, who retired from tennis earlier this year to spend more time with her family, posted a picture on social media on Saturday showing the couple's first two children, Blake and Andie, holding silver '1' and '2' balloons, with a third numbered balloon positioned above a blackboard displaying the message 'Coming March 2019' and showing a scan of the impending arrival.

"Baby, ohhhhhhh," she posted on Instagram, alongside three baby emojis. "Surprise. It’s my turn to carry our child this time. Amanda and I are so excited to share with you all we will be growing our family by one. ETA March 2019 #babyonboard #partyoffive #family #boyorgirl #17weekspregnant #familygoals #tookanhourtogetthisphoto #50takeslater #lol @amandakjudd."

The news follows former World No.1 Martina Hingis announcing her pregnancy on her birthday last week, while three-time Grand Slam doubles champion Elena Vesnina is also expecting.

Judd carried the couple's first two children while Dellacqua continued her tennis career, with Blake born in August 2013 and Andie arriving in April 2016.

Dellacqua left the sport this year having reached a singles ranking of 26 in 2014 before giving more time to her doubles career following a head injury.

She partnered Scott Lipsky to the mixed doubles at the 2011 French Open, having also made seven women's doubles grand slam finals, including three at Roland Garros.

Last year, together with Barty, the pair became the first all-Australian women's pairing to make the final at Roland Garros in 46 years - and also became the first Australian duo in the Open Era to qualify for all four of the women's Grand Slam doubles finals.

In singles, she also twice made the fourth round of the Australian Open, in 2008 and 2014, and also reached the last 16 of the US Open four years ago.

The pair were quickly congratulated on the news by fellow members of the tennis community, such as Kim Clijsters, Anne Keothavong and Judy Murray.