The couple made their first public appearance since announcing their happy news last week by heading to London's Oxford Street for the launch of Disney Store's Share in the Magic charity campaign.
They were joined by a handful of other famous faces including Michelle Heaton and her daughter Faith and Denise Van Outen and her daughter Betsy.
However, instead of hobnobbing with their fellow celebs, Tom and Giovanna got stuck into some shopping for unborn little one and were caught browsing the fun-filled store for clothes and toys.
The pair also posed for a cute snap with Mickey and Minnie Mouse and were even invited to post a letter to Santa.
Giovanna covered her baby bump with a loose fitting patterned dress and kept warm with a long black coat and some thick tights. She also chose to wear a comfy pair of black boots and accessorised with a small pendant necklace.
Meanwhile, McFly singer Tom - who also writes children's books with bandmate Dougie Poynter - looked cosy in a shearling red jacket, which he teamed with faded black jeans and a check shirt.
The pop star and his wife married last year in an intimate ceremony in front of family and close friends.
They announced their exciting baby news at the end of October via a super sweet Halloween themed video, in which they carved the words 'We're having a baby' into pumpkins.
Tom has since said that this is the "most excited" he's ever been in his life. And judging by all of his shopping bags, it seems like he's already preparing to spoil his first child rotten!
The Share in The Magic Charity campaign is a nationwide campaign that invites families to post their own Letter to Santa in store and online at Disneystore.co.uk.
For every letter posted, Disney Store will donate a soft toy to a variety of local children's charities, with central London stores donating toys to Great Ormond Street Hospital Children's Charity.
Watch Tom and Giovanna's baby announcement video below.