Frankie, who is expecting her first baby with footballer fiance Wayne Bridge, appeared in London's Hyde Park yesterday (7 July) for the British Summer Time festival.
The singer's LBD had a sheer dipped hem and pink detailing around the bust, and she teamed it with a bright red jacket to add a contrasting pop of colour.
Last month, Frankie swapped her crop for long hair extensions but it seems she has since had a little bit of the length snipped off, as her locks fell just above her shoulders.
Frankie's fellow bandmates - Rochelle Humes, Una Healy, Vanessa White and Mollie King - all looked super summery in bright colours and posed together backstage for pictures.
In May, Rochelle gave birth to her daughter Alaia-Mai and, dressed in a leopard print mini skirt and yellow sleeveless top, we think she's already got that yummy mummy look down to a tee!
Michelle Keegan, Victoria Beckham, Tulisa: Top showbiz stories from 6/7 July in pictures: