Natalie Portman was a vision in white when she attended Vanity Fair's post-Oscar party held at the Sunset Tower in West Hollywood, Calif. on Sunday. 

The dress she wore to the event, however, sparked rumors that she might be pregnant again. The actress wore a white strapless Christian Dior gown with with an empire-waist that flowed loosely just below her chest. The loose fit caused speculation that she might be hiding a baby bump. Portman wore a dress with a similiar empire-waist shape to the Oscars in 2011 when she won the Best Actress Academy Award for her role as the deranged ballet dancer in the 2010 film Black Swan.

Portman, 31, accessorized her loose Christian Dior dress on Sunday with emerald green drop earrings by Anna Hu. The actress attended the event with her husband, ballet dancer and choreographer Benjamin Millipied.

Portman began dating Milliped, 35, on the set of Black Swan in 2009. In December 2010, Portman announced their engagement and confirmed her pregnancy. She gave birth to their son Aleph Portman-Millepied in June 2011 and the couple revealed they were married when they attended a post-Oscars bash last year wearing wedding rings.

A friend of Portman's revealed last fall that the actress is taking a break from acting for a while because she wants to enjoy being a married mother-of-one.

"Natalie is being super choosy about her projects and taking more time off from acting," an insider to Us Weekly. "She has this glow about her these days. There's been a change in her since the little man arrived. She and Benjamin are so content." 

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