Christina Aguilera Shows Off Major Curves

 Denise Truscello/; Jon Kopaloff/FilmMagic

Christina's got curves.

Clad in a form-fitting Atelier Versace frock, the 29-year-old mother of one looked curvier than ever at a bash at the Los Angeles County Museum of Art over the weekend.

It was a startling contrast from the singer's svelte figure a few months ago.

A source tells Britain's Daily Mail that "it's bizarre Christina has put on so much weight as she's been doing lots of dancing and high energy work for Burlesque [out in November]. The whole movie is choreography and she was very active so I'm surprised she's piled on the pounds so quickly."

In 2008, Aguilera — who just returned from Nicole Richie's Mexican bachelorette bash — told Us Weekly she felt "a sense of accomplishment" after shedding 40 lbs. she gained during her pregnancy with son Max, now 2. At the time, her weight loss plan included cardio workouts, weight training, and stretching five times a week. She also followed a strict protein, veggie and whole grain diet.

In July, she said in the U.K. magazine Company that whatever size women are, "we shouldn't be ashamed of ourselves or our bodies."

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