Even though she hasn't officially announced that she's expecting, Gwen Stefani showed off her pregnancy curves at the Opening Night Gala of the Wallis Annenberg Center for the Performing Arts in Los Angeles on Thursday.

The singer, 44, looked glamorous in the floor-length beaded Ferragamo gown. She wore her platinum blonde locks in a knotted updo.

A source told Us Weekly: "She had a huge glowing smile on her face and was totally having fun...Gavin held her hand very attentively and admirably."

Stefani's pal Eve accidentally revealed the pregnancy news in September. "She's preggers," the singer told Live Nation.

The baby will be Stefani and her rocker husband Gavin Rossdale's third child. They have two sons: Zuma, 5, and Kingston, 7.

Check out more photos of Gwen...