Well, she hasn't said so, but if you look at these pictures - is there really any denying it?
LAMB designer Gwen, 44, who already has sons Kingston, seven, and five-year-old Zuma with her husband, Bush vocalist Gavin Rossdale, made the big reveal on Thursday night as she clutched her impressive bump over her fringed frock for the world to see.
With Gav by her side, the Hollaback Girl singer looked radiant as she rocked her blue shimmering floor-length Ferragame dress on the red carpet at the Wallis Annenberg Center for the Performing Arts Gala in Beverly Hills.
With her platinum blonde hair in a chic up-do and her signature red lipstick on, Gwen looked oh-so glamorous on the arm of her velvet-clad man.
The couple, who have been together for 11 years, were surrounded by A-listers including Nicole Richie, Courteney Cox and Demi Moore at the event.
We have contacted a representative for Gwen for comment.