The actress, who is earning acclaim for her performance in The Imitation Game, is pregnant with her first child, Page Six reports.
The newspaper reports that Knightley, who married rocker James Righton last year, is more than three months along.
Knightley, 29, earned two SAG Award nominations, for Outstanding Performance by a Female Actor in a Supporting Role and Best Ensemble, and a Golden Globe nod for Best Supporting Actress for playing part of the code-breaking team led by Alan Turing (Benedict Cumberbatch) during World War II.
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