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has won praise for her simple, chic maternity style.
As the expectant actress celebrates her 30th birthday, HELLO! Online
takes a look at the star's pregnancy style.
Olivia was glowing on the red carpet at this year's Oscars on the arm of fiancé Jason Sudeikis.
The mum-to-be flaunted her baby bump in a high-neck, black and white Valentino gown, topping off the look with diamond chandelier earrings and a side-swept updo.
For an appearance late last year, Olivia dressed her bump in a cobalt blue dress with silver mirror details.
Attending the Golden Globes, Olivia dazzled in a green sequin floor-length dress. She revealed the due date of her little one to presenter Ryan Seacrest.
"May the fourth be with you," she laughed after being asked when she was expecting her first child with fiancé Jason Sudeikis to arrive.
Olivia and Jason announced their happy news
back in October of last year.
"They are incredibly happy," a source close to the couple told People magazine. "They're very excited to welcome a new member into their family."
The Rush actress took to Twitter to thank fans for their well-wishes following the announcement of the happy news.
"WOW. You guys are awesome. So kind. Thank you thank you thank you! PS. Babies eat mostly salsa right?"
The 29-year-old actress, who has not disclosed her due date, first met 38-year-old actor Jason on the season finale of Saturday Night Live back in 2011.
The pair began dating six months later and got engaged in January of this year, according to People. They are set to wed in New York next spring.