Mario & Courtney Bring Their Baby Bump to Bikini Bash

Cosmopolitan Magazine's third annual "Bikini Bash" brought out the stars and the baby bumps in Las Vegas! Guest host Mario Lopez and his girlfriend Courtney Mazza posed with their baby bump on the carpet. Host Holly Madison kept the bash lively while guest host Lauren Bosworth showed off her long black cover-up!

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The bash went down at Planet Hollywood Resort & Casino in Las Vegas on Monday and seemed to be a success.

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But the happiest stars there were parents-to-be Mario & Courtney!