Former X Factor star Rebecca posted the snap on Instagram last night (19 June) and confirmed she will call her unborn child Arabella.
However, while revealing her news, the singer's post appeared to be touched with sadness, as she insinuated that people had previously advised her not to have the baby.
Alongside the ultrasound image, Rebecca wrote: "You wasn't expected you wasn't planned [sic] but I'm thankful that I was chosen to bring you into this world.
"Feel a special bond because when everybody said you was wrong I fought for you, i held my ground and said every child has a right to live.
"Feel like god blessed me with someone who I know will always bring me joy my princess my precious unborn arabella xxxx."
Shortly after fainting on Loose Women, Rebecca announced that she was pregnant with her third child in April.
The Liverpudlian, 27, already has two children from a previous relationship and has not disclosed who the father of her unborn baby is.
Celebrities who have announced pregnancies in 2014:
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