The 21-year-old EastEnders actress donned a figure-hugging onesie for the photo, which flattered the curve of her expanding belly.
"Baby bump," Jacqueline captioned the picutre. "#onsie #cosy #messydressingroom."
Jacqueline will welcome her first child early next year
Last week Jacqueline shared the first picture of her baby's scan with her Instagram followers when she and her partner, TOWIE star Dan Osbourne, hosted a celebratory party to mark finding out the gender of their first child.
Pictured next to the scan was the couple's 'baby reveal cake', a popular style of cake offered at baby showers where the sponge inside is dyed blue or pink to indicate whether the baby is a boy or a girl.
While the parents-to-be posed for a picture with a slice of the cake, which was iced with the phrase "twinkle, twinkle little star... how we wonder what you are?", they kept their fans guessing about the sex of their baby by filtering the picture black and white.
Jacqueline and Dan have kept their fans guessing about their baby's gender, despite having a 'baby reveal cake'
Dan and Jacqueline revealed they were expecting their first child together in August, released a joint statement saying that they were "thrilled by our news".
The 23-year-old TOWIE star - who welcomed son Teddy in December with ex-girlfriend Megan Tomlin - added, "Becoming a father has been the most amazing thing to ever happen to me. I can't believe I'm going to be a dad again – I'm truly blessed."
A spokesperson for EastEnders also offered their congratulations to Jacqueline, who plays Lauren Branning in the soap.
"Everyone at EastEnders is thrilled for Jacqueline," said the rep.