The beautiful former House and The OC actress looked cute and casual in jeans and a loose shirt as she enjoyed lunch with friends on Monday (16 December).
Olivia and her fiance Jason Sudeikis announced at the end of October that they are expecting their first child together, but have kept quiet on any additional details.
The 29-year-old's schedule hasn't slowed down following her announcement.
Last week she was on hand to help announce the nominees for The Golden Globe Awards 2014 and attend the premiere of her latest movie Her in Los Angeles.
She's even found time to impart some beauty wisdom, telling People magazine that a clearly defined brow is the staple of her everyday routine.
"It changes your face so much when you have your eyebrows filled in and softened," she said. "I spent years trying to look like Kate Moss with wispy thin eyebrows, which was a horrible mistake and everyone told me not to do it. So now I'm obsessed."
More pregnant celebrities in Reveal's gallery below!
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