Tamara is expecting her first child with husband Jay Rutland and they joined their family and friends for a celebratory dinner on Saturday night.
The meal was held for Jay's birthday at 'C' restaurant in London's exclusive Mayfair and guests included Tamara's sister Petra, who became a mum herself last year.
Posing outside the eatery with her husband, Tamara was all smiles as she showed off her bump and bare legs in the black maternity number.
Last June, Tamara married Jay in a lavish three-day wedding in the French Riviera , which is rumoured to have cost around £7 million.
Three months later, Tamara announced that she was pregnant with their first child.
It is thought the couple are expecting a baby girl, after Petra made pink invites for Tamara's shower.
Celebrities who have announced pregnancies in 2014:
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