The 39-year-old shared her happy baby news via Twitter this morning shortly before confirming the pregnancy on air.
Charlotte wrote: "I'm delighted to announce some breaking news of my own on @gmb this morning - I'm pregnant! Big thanks for all the lovely messages xx."
On Good Morning Britain, she revealed the baby – which is her first – is due in February.
And she shared she's already craving chocolate and biscuits.
Co-presenter Susanna Reid later tweeted a picture of Charlotte holding her stomach. We can't really see a sign of a baby bump yet though!
"Congratulations to our lovely Charlotte, expecting her first baby," said Susanna. "The best news."
Charlotte has been married to businessman husband Mark Herbert for five years. They were dating for a decade before tying the knot.
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Stars who welcomed babies in 2014 in pictures:
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