The One Show star, 44, shared a smiling photograph from the hospital bed in the early hours of Saturday morning with her 305k Instagram followers.
In the snap, the pregnant beauty posed with her husband Charlie Thompson.
They have been preparing for their third baby and their first baby girl together.
She wrote: “Just been brought in to have a bit of monitoring… Nothing exciting so far.”
In recent weeks, the presenter went on maternity leave from her job at The One Show.
In her last episode before her maternity leave, she was left close to tears after The One Show played a beautiful montage of tributes for the star.
She said in August: “Oh well you know me I cry at the slightest thing, but it has been honestly, being here has just been superb I have loved doing it every night.
“I just want to say a big thank you to everyone who has knitted lovely gifts for the baby, there is about 24 cardigans, she is going to be in cardigan heaven this little girl.
“I’ve loved every minute, it is very hard to leave.”
At her London home, she lives with her husband as well as their two children Edwards, four, and Kit, two.
She announced her pregnancy joy to fans in March.
In recent months, Mrs Jones gushed over her miracle pregnancy.
She told The Mirror: “We’ve been super lucky to fall pregnant for a third time.”
She added: “I didn’t realise how much it did mean when it said the foetus is female. Charlie said, ‘I’ve never seen your face like that.’ I think I’d been trying to bury it, thinking it would be lovely either way. It’s easier for the boys, they’ve become so close as brothers.
“They’ve got their own little relationship, a solid little team and explaining a girl is a bit easier for them to understand. Three children in four and a half years.”