Posing in her underwear in front of a mirror, Abbey's hip and thigh bones stuck out in the snap, causing a flurry of comments from fans worried about her weight.
The 27-year-old model, who later deleted the tweet, has previously been plagued by rumours of anorexia after shifting her pregnancy weight in record time in 2011.
At the time, Abbey revealed that she weighed less following the birth of her daughter Sophia than she did before she fell pregnant.
She said: "I weigh less than I weighed before I had the baby and I’m really happy with my figure. I’m lucky to be blessed with good genes.
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"My mum is 51 and hasn’t had any work done but she still looks like she could be my sister. She’s a goddess."
Abbey tried to silence her weight critics last week by retweeting a snap of herself eating a massive hot dog on a shoot in Liverpool.
But even Nicola McLean, who has previously battled both anorexia and bulimia, recently expressed her concern over Abbey's plummeting weight when she saw snaps of the model in a bikini.
She tweeted: "She is soooo thin it's worrying [sic]"