Pregnant Tamsin Egerton is super chic in figure-hugging little black dress as she cosies up to Donna Air at glam dinner

She's expecting her first child in a couple of months, and has been showing off an enviable pregnancy wardrobe since the summer.

And as Tamsin Egerton hit the Baccarat/1 Hotel Dinner at One Horse Guards in London on Wednesday night, the British actress and girlfriend of US star Josh Hartnett was again looking effortlessly chic.

Tamisin, 26, kept her look simple in a little black dress which showed off her neat baby bump as she enjoyed the glam dinner with the likes of Donna Air.

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Glam mum-to-be: Tamsin Egerton hit theBaccarat/1 Hotel Dinner at One Horse Guards in London on Wednesday night

Glam mum-to-be: Tamsin Egerton hit theBaccarat/1 Hotel Dinner at One Horse Guards in London on Wednesday night

The blonde beauty looked gorgeous in her knee-length number which featured a flirty pleated skirt and three quarter length sleeves.

The high-necked frock was teamed with classic black heels and a chain-length shoulder bag.

Tamsin left her long blonde locks loose and swept back from her face to accentuate her pretty features, adding a touch of lip gloss and shimmering eyeshadow. 

Tamsin and Josh, who have been together since 2012 after meeting on the set of their film The Lovers, are happily counting down the days till they welcome their first child.

Chic: Tamisin, 26, kept her look simple in a little black dress which showed off her neat baby bump as she enjoyed the glam dinner

Chic: Tamisin, 26, kept her look simple in a little black dress which showed off her neat baby bump as she enjoyed the glam dinner

Blonde beauties: Tamsin was without her boyfriend Josh Hartnett but instead mingled with Donna Air, who was looking gorgeous in a peacock print midi-length dress

Blonde beauties: Tamsin was without her boyfriend Josh Hartnett but instead mingled with Donna Air, who was looking gorgeous in a peacock print midi-length dress

Josh and the model-turned-actress started dating shortly after he was in a romance with American actress Amanda Seyfried. 

The US actor and Brit beauty now split their time between Dublin, where Josh films his hit TV show Penny Dreadful for six months of the year, and London where Tamsin has a home.

Josh's representative confirmed their baby joy in July, by tellingPage Six: 'It's true and they are beyond thrilled.'

Just a few months before the news broke, 37-year-old Josh revealed he was looking forward to being a father.

Pretty in print: The TV star showed off her svelte figure in the statement dress teamed with brown shoes

Pretty in print: The TV star showed off her svelte figure in the statement dress teamed with brown shoes

Stylish night: Tamsin looked pretty with her blonde locks swept to the side as she chatted with fellow dinner guests Guy Pewsey and Laura Seward-Smith

Stylish night: Tamsin looked pretty with her blonde locks swept to the side as she chatted with fellow dinner guests Guy Pewsey and Laura Seward-Smith

He told Playboy: 'I have to get a car that's safe for my kid. I don't have a kid yet, but that's the idea coming into my head these days.' 

While Tamsin was without her man on Wednesday, she did mingle with a glam crowd, including Donna Air.

The TV star was looking gorgeous in a peacock print midi-length dress, which highlighted her svelte figure.

With a pair of brown satin pumps and a clutch to finish off the ensemble, Donna left her glossy blonde locks in loose waves as she hit her second event of the night, after enjoying the Very.co.uk fashion presentation with her daughter Freya. 

Not long now! Tamsin , who has been dating Josh since 2012 after meeting on the set of their film The Lovers, is happily counting down the days till she welcomes their first child

Not long now! Tamsin , who has been dating Josh since 2012 after meeting on the set of their film The Lovers, is happily counting down the days till she welcomes their first child

Mingling: Donna cosied up to Yasmin Mills, Melissa Odabash and Lara Bohinc over drinks and dinner

Mingling: Donna cosied up to Yasmin Mills, Melissa Odabash and Lara Bohinc over drinks and dinner

Party hopper: Donna, pictured with Roy Luwolt, was hitting her second event of the night, after enjoying the Very.co.uk fashion presentation with her daugther Freya earlier in the evening

Party hopper: Donna, pictured with Roy Luwolt, was hitting her second event of the night, after enjoying the Very.co.uk fashion presentation with her daugther Freya earlier in the evening

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