The 'Skyscraper' singer gave a thumbs up to photographers outside the plush Kensington Roof Gardens on Wednesday (9 April) ahead of performing at the Jog On To Cancer event.
Sam highlighted her ever-growing baby bump in a slinky black dress that fell to the knee, teamed with skyscraper (no pun intended!) heels and a sleek updo.
The former prison guard was among a string of stars who performed at yesterday's event, which raised money and awareness for Cancer Research UK - and her set certainly went down well with guests!
TOWIE star Jessica Wright tweeted: "It doesn't get better than this @SamBaileyREAL."
X Factor's tenth winner Sam announced in March that she's pregnant with her third child. She learned the happy news after taking a pregnancy test in the toilets of Asda while shopping with husband Craig.
As well as celebrating a pregnancy, the 36-year-old is also celebrating professional success.
Her debut album The Power of Love topped the album charts on Mother's Day, becoming the fastest-selling album of the year so far and the first X Factor winner's album since Alexandra Burke to be number one, and, of course, her debut single 'Skyscraper' was Christmas number one.
Sam has just wrapped the 'X Factor Live Tour' and will hit the road on a solo tour next year.
She'd initially planned a string of dates for later in 2014 but news of her pregnancy has postponed those shows until the following year.
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Celebrities who announced pregnancies in 2014 in pictures:
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