The TV presenter arrived in south west London in a pretty floaty cream dress with an embroidered neckline.
It's no surprise, then, that she was recently named celebrity with the best-dressed baby bump, beating Kimberley Walsh and Kourtney Kardashian in the process, reports the Daily Mail.
Holly was joined at Fearne's wedding by her husband Dan Baldwin, and her fellow Celebrity Juice co-star Keith Lemon.
The This Morning star already has two children, Harry, five, and Belle, three.
She is good friends with Fearne, who married her musician boyfriend Jesse Wood on Friday at the Richmond Register Office.
The Radio 1 DJ looked stunning in a ruched white gown by Pucci, with a glittering silver sequinned neckline. She paired the gown with amazing silver strappy stilettos and a jewelled headband.
Other stars at the wedding included members of McBusted, Kirsty Gallacher, Denise Van Outen and Amanda Byram.
Jesse's Rolling Stone dad Ronnie Wood also attended the ceremony with his wife Sally Humphreys, whom he married last year. His ex-wife Jo Wood was also in attendance.
MORE YUMMY MUMMY STYLE ! See more stars who are expecting or have already welcomed babies in 2014:
More:Have You Seen?
Suggested For You
SUBSCRIBE AND FOLLOW
Get top stories and blog posts emailed to me each day. Newsletters may offer personalized content or advertisements.Learn more