The McFly singer, 28, wished his "gorgeous" wife a happy birthday on Twitter by uploading a photo of Giovanna and her growing baby bump.
"A very happy birthday to my gorgeous wife and bestest good friend in the universe," wrote Tom to his 1.23million followers. "Looking gloriously pregnant :)."
Giovanna is pictured sitting in the car, beaming away at the camera and getting ready to go into her baby scan. Tom kept the couple's fans updated on their movements, by tweeting that he "[loved] seeing the little mini Fletcher."
Apart from having her scan, it looked like HELLO! Online blogger Giovanna was going to spend a large part of the day indulging.
"Thanks for all your lovely messages! As many of you have requested — I promise to eat lots of cake today. ❤ Xxx," wrote the birthday girl.
In her latest blog post, the 29-year-old author revealed how she and Tom have been preparing for the arrival of their baby, who they've taken to affectionately calling "Crumb."
"This week Tom and I took ourselves off to Mothercare to get a whole heap of essentials for Crumb (a huge thank you to the staff at the Watford store who managed to answer all of our silly questions!)," wrote Giovanna.
"I just wanted to get my hands on everything so that I could start nesting properly. Ha! Believe it or not, the item most recommended by you mummies out there was Sophie the Giraffe, so I'm happy to say Sophie is settling into her new home very nicely!
"I'll keep you posted on how the nursery is coming together over the next few weeks — so far we've emptied it of everything that was in there… Like I said, weve made a start."
The couple announced that they were expecting their first baby in October, with Giovanna's expected due date in March.