Holly, who is expecting her third child with producer husband Dan Baldwin, was pictured on the back of a motorbike as she left a photoshoot in London.
The 33-year-old television personality was seen smiling and waving goodbye as she hopped on her ride, securing her safety helmet in place.
Holly had spent the day at the Ideal Home Show, where she was promoting her BHS bedding collection with a photo-call. As she left the Earls Court exhibition centre, the pregnant star opted for a more casual all-black ensemble.
Photos from her shoot show Holly looking picture-perfect in a blue and white polka dot dress. The television presenter and model strikes a variety of poses as she sits on a made-up bed and stands to the side to show off the linens range.
A glowing Holly wore her blonde hair loose in waves around her shoulders, framing her heart-shaped face.
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Last November, the mother-of-two launched the high-street collection and at the time donned a sheer white polka dot frock with a champagne coloured waist belt.
Holly said that the home design project was "something that [she'd] wanted to do since [she] was a little girl decorating [her] doll's house," according to the department store's website.
Holly and Dan — who are parents to Harry, four, and two-year-old Belle — are looking forward to adding to their brood.
Was Holly showing signs of morning sickness?
"Surprise Surprise (and it was a surprise!!), I'm really happy and excited to tell you that Dan and I are expecting baby number 3!!" wrote Holly on her official website OfficialHollyWilloughby.com.
"We feel blessed and very lucky to be giving Belle and Harry a little brother or sister later this year. Xxx."
The couple married in August 2007, with fellow television personalities Fearne Cotton and Sarah Cawood acting as bridesmaids. X Factor host Dermot O'Leary played the usher.