The beautiful actress stood out from the crowd in a bright Soul Cycle gym top when she was snapped in Los Angeles on Monday (27 January).
29-year-old Olivia is expecting her first child with actor fiancé Jason Sudeikis. They announced at the Golden Globe Awards earlier this month that the new arrival will be a boy.
The due date is thought to be 4 May, after Olivia revealed she remembers the date by using the phrase, "May the fourth be with you", which marks Star Wars Day.
Olivia - who shot to fame in TV shows The O.C. and House - can next be seen in the indie movie Better Living Through Chemistry.
Co-starring Sam Rockwell and Ray Liotta, the movie is about a pharmacist who lives a relatively dull life until he starts an affair with a customer.
Celebrities who announced pregnancies in 2014 in pictures:
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