The happy couple announced their amazing news on Monday (25 August) saying they were "thrilled".
Catherine, who plays Eva Price in the ITV soap, told her Twitter followers: "Delighted to tell you all that @TP_PTfitness and I are expecting a bambino! Beyond thrilled :-)."
Messages of congratulations flooded in for the pair, with one telling Catherine "you will be a yummy mummy".
Another fan said: "Ooooh how wonderful, amazing news, such an incredible journey enjoy every moment both."
The actress, 30, and her fitness trainer boyfriend, 27, met at Hale Country Club, Cheshire, where he works.
She split from personal trainer Sam Witter, 23, in April last year before meeting handsome Tom.
Ever since losing nearly five stone to win the part in Corrie, Catherine has become a fitness bunny and enjoys healthy eating.
In June, Catherine and Tom took part in the Great Swim for charity at Lake Windermere (when she must have already been a little bit pregnant!).
A huge congrats to you both!
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