Looks like Christina Aguilera's wardrobe missteps don't stop at pantless ensembles.

PHOTOS: Stars who step out without pants

At the 2011 American Music Awards in Los Angeles Sunday, the singer joined Maroon 5 on stage during "Moves Like Jagger," clad in one of Herve Leger's curve-hugging bandage dresses, which she teamed with sky-high Christian Louboutin heels and a wildly frizzy hairstyle.

PHOTOS: What all the stars wore at the 2011 AMAs

The songstress, her major cleavage and silver skin-tight mini instantly received backlash on blogs and Twitter, sparking speculation that the 30-year-old, who's already a mom to one, may be pregnant.

PHOTOS: Christina Aguilera's Crazy, Sexy Music Video Style

Fans and critics in the cyber world aren't the only ones who've been slamming Aguilera for her fluctuating weight. In August, Kelly Osbourne had some choice words for the star on an episode of E!'s Fashion Police.

PHOTOS: Stars who've been bullied for their weight

"Maybe she is just becoming the fat bitch she was born to be," Osbourne, 27, chimed in after Joan Rivers criticized the singer for a too-tight outfit. "I don't know. She was a c**t to me. She called me fat for so many f***ing years. So you know what? F**k you! You're fat too."

Tell Us: Do you think Aguilera should have picked a better-fitting dress?

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