The pregnant Gossip Girl star looked incredible as she posed for the cameras on the black carpet at New York's The Pierre Hotel last night.
Blake, 27, was without actor husband Ryan Reynolds, but had no shortage of people to mingle with with guests at the bash including Eva Longoria, Diane Keaton and Julianne Moore.
Actress Blake was named the new face and hair of L'Oréal Paris back in October last year, joining a glittering list of ambassadors including Eva and Jennifer Lopez.
At the time, she said: "I am thrilled and honoured to join the incredible women who represent L'Oréal Paris. From the versatile and motivational brand ambassadors, to all the women who proudly wear L'Oréal Paris each day."
"I grew up with the inspiration of their message: "We're worth it". What an important value to instill in women. That beauty is rooted in confidence. That is key. That is why I'm so proud to be a L'Oréal Paris woman."
Blake announced her first pregnancy two months ago, discreetly releasing the news via a simple image of herself sporting a baby bump on her Preserve website.
She's been married to Green Lantern star Ryan since 2012.
Stars who announced pregnancies in 2014!
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