The royal was without rugby playing husband Mike Tindall at yesterday's event, but had no shortage of people to talk to thanks to the glittering guest list of Olympians.
Zara, 32, joined fellow Olympians including Jessica Ennis and Victoria Pendleton at the glitzy gala on Wednesday evening (30 October), celebrating 100 days until the start of the 2014 Olympic Winter Games.
She won a silver medal as part of the Great British Eventing Team at the London 2012 Olympics, but is currently not competing professionally due to her pregnancy.
Zara and Mike married in 2011 and announced earlier this year that they're expecting their first child together in early 2014.
In an interview with Australian Women's Weekly this month, the couple said they've decided not to find out the sex of the baby until its birth.
Mike also joked of the pregnancy: "It probably happened quicker than we thought. [It was a] bit of a shock, really."
The couple will be able to turn to Zara's cousin Prince William and his wife Kate for advice as they welcomed their first child together, George, in July 2013.
Last week it was revealed that Zara had been chosen as one of Prince George's seven godparents.
More stars expecting babies in our gallery below!
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