Jennifer Lopez brought some old school glamour to the red carpet at the premiere of What To Expect When You're Expecting.

The actress joined the film's all-star cast, including Cameron Diaz, Matthew Morrison and Chace Crawford at Grauman's Chinese Theatre in Los Angeles.

And, with her toyboy beau Casper Smart on her arm, the 42-year-old won top marks for style in a full-length Maria Lucia Hohan Grecian gown which plunged down to the waist.

J-Lo's co-star Rodrigu Santoro was full of praise for the singer and actress, who he described as a "sweetheart".

The pair appear as a couple preparing to adopt a baby in the romantic comedy, which also stars Elizabeth Banks and Chris Rock.

He said: "We had a great time, she's a sweetheart."

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