The French actress, who is famous for her role of Shosanna in Quentin Tarantino's 'Inglourious Basterds', wore a simple black maxi-dress for the May 21 event and cradled her belly while being photographed, the Us magazine reported.
Laurent, 30, is married but declined to name her husband. In a March interview with the Independent, Laurent said her husband was a crew member.
"With my boyfriend/husband, I say that because I don't like the word husband, he was a crew member and I was an actress and we would look at each other seductively for a few days before we talked," she said.
The actress was linked to Bradley Cooper in 2011 after they were spotted roaming the streets of Paris.