Pregnant Frankie Sandford covers up in a billowing top and loose trousers as she joins her basque-wearing Saturdays bandmates at the Summertime Ball

Revealing tops and thigh-skimming miniskirts are wardrobe essentials when it comes to The Saturdays' on-stage ensembles.
But pregnant Frankie Sandford opted for a more conservative look as she joined her bandmates at the Capital FM Summertime Ball on Sunday.
Instead of sporting the same cleavage-baring basque tops as her bandmates, Frankie opted for a more comfortable billowing vest top and loose black trousers.
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Still smiling! Frankie grinned from ear to ear as she busted a move on the stage

Covering up: Pregnant Frankie Sandford opted for a loose-fitting top and trousers in contrast to her Saturdays bandmates' revealing basque tops and shorts at the Capital FM Summertime Ball on Sunday

Posing up: Mollie posed with band mates Una Healy, Vanessa White and a pregnant Frankie Sandford ahead of the performance

The 24-year-old singer did, however, add some glamour to her ensemble by wearing a pair of sky-high heels and wearing her new long hair loose in tumbling curls.

 

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Pregnant Frankie Sandford joined the Saturday's on stage in loose...

And when Frankie took to the stage to perform hits including All Fired Up with the girls, she did reveal a bit more as she flashed the fluorescent pink bra she was wearing under her top.
However, Frankie's footwear choice perhaps wasn't the best option for a long day of hard work, as the singer tweeted her fans that she was enjoying some of the perks backstage at the Wembley Stadium event.

Blooming: Frankie is expecting her first child with fiancé Wayne Bridge

Playing it safe: Despite her relatively conservative outfit, Frankie added some glamour with a pair of sky-high heels

She wrote: 'Having an amazing foot massage backstage while listening to The Wanted sound check. I suppose someone's got to work! Lol.'
When it came to their wardrobe choices, Frankie's bandmates didn't follow her example by covering up.
Mother-of-one Una Healy upped the sexiness of her outfit by teaming her metallic corset-style top with a pair of high-waisted pink hotpants and shoe boots.

Strutting their stuff: The girls looked in good spirits as they took to the stage

Hot pink: Frankie flashed a hint of bra as she performed, while Una was working her metallic top

Nautical but nice! Vanessa showed off her slim figure in her top and paper-bag top trousers

Mollie King opted for a similar look in her ensemble, as she paired her top with silky purple shorts.
Vanessa White, meanwhile, appeared to be in solidarity with pregnant Frankie, choosing to wear her top with a pair of loose-fitting purple trousers.
Absent from the occasion was Rochelle Humes, who is still on maternity leave following the birth of her daughter Alaia-Mai - her first child with husband Marvin Humes.

Leggy ladies: Una and Mollie both opted for shorts to show off their enviable figures

Cleavage-baring: The girls didn't hold back with their revealing top choices

Make-up fans: Frankie and Vanessa certainly didn't hold back with their make-up for the occasion

You look different! Marvin Humes made up for his wife Rochelle's absence from the event as he posed up with her bandmates

But Rochelle's absence in the group was made up for by former JLS star Marvin, who opened the star-studded event with an energetic DJ set.
And tweeting a picture of himself with The Saturdays, Marvin wrote: 'They're missing my baby @RochelleTheSats don't worry Roch I'm gonna fill in today!!! X'
Rochelle later tweeted on her own account: 'Good luck to @TheSaturdays and @MarvinHumes performing @ the @CapitalOfficial Summer time ball. Love u lots xxxxxx'

Hit makers: Nathan Sykes rejoined his band The Wanted on stage at the Summertime Ball after being off sick following emergency throat surgery

Giving it his all: The 20-year-old sang his heart out for the crowd as the band performed

Good to be back: Tom Parker was seen jumping on Nathan, clearly excited to have the full band back together

The Wanted kicked off the action at the Wembley Stadium, with Nathan Sykes making a welcome return to the group following emergency surgery on his vocal chords. 
The 20-year-old singer joined the band on stage at the event for the first time in weeks, after suffering a hemorrhaging nodule.
Nathan seemed delighted and somewhat overcome with emotion to be back performing, later thanking his fans on Twitter.

Let me here you: Nathan loved his time on stage, following weeks of rest and recuperation

Hi tracks: The quintet performed some of their biggest hits including All Time Low and Glad You Came

What a flirt: Max was seen eyeing up a pretty dancer as he sang away with his band in front of the 80,000