"Thanks for all your warm wishes," Wood, 25, wrote on her Twitter account. "We are very happy. I'm gonna be a mama!"

Moments earlier, Wood posted a picture of the pregnancy book "What to Expect When You're Expecting" on the social media site.

It will be the first child for both Wood and Bell, who wed in October.

Wood rose to Hollywood stardom for her roles in 2008's "The Wrestler" and the 2003 coming-of-age drama "Thirteen." She was nominated for an Emmy award for the 2011 television mini-series "Mildred Pierce."

Bell, 26, found fame as the teen star of "Billy Elliot," about a ballet dancer growing up in a tough coal mining town in northern England. He won a British BAFTA award for the role and has since appeared in adventure movies such as "The Eagle."

(Reporting by Eric Kelsey; editing by Philip Barbara)

• A Permanent Economic Emergency