The Olympic swimmer, 26, shared a cute baby bump snap with her husband Harry Needs - but HIS bump is bigger than hers!
In a photo shared with her 500,000 Twitter followers, gold medallist Becky joked that the couple were having a "bump-off".
The I'm A Celebrity star, who has carried on keeping fit while pregnant, can be seen surrounded by exercise equipment in an otherwise empty gym.
Flaunting her bump in tight workout gear, she is camera ready as her husband poses beside her with a matching round belly!
The personal trainer has either defied the laws of biology, eaten a rather large lunch... or stuffed a ball down his vest!
Alongside the snap, Rebecca said: "He's so competitive, he had to have the bigger bump!! #whoworeitbest #bumpoff @harryneeds."
The likeable couple - who wed last year - have kept their fans updated on her pregnancy since announcing the good news in December.
Just last week, Becky shared a cute photo of Harry kissing her bump as they enjoyed a relaxing break in Dubai.
Rebecca is expected to give birth in June.
She has previously revealed plans to have a water birth.
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