"Wayne and I are so proud to say our little boy Parker Bridge was born this morning," tweeted the new mum. "7lb 13oz. All doing well and absolutely besotted ❤😍️"
Frankie's band mate Vanessa White was the first of The Saturdays to Tweet her congratulations to Frankie.
"@FrankieTheSats a massive congratulations to you and Wayne!!" wrote Vanessa. "I'm so excited to meet Parker!!! ❤️ wooo!! Xx."
Frankie had hinted in recent days that she was anxious for the new arrival – as were her friends and family.
"I can no longer call anyone without them going into a panic that I've gone into labour!" she tweeted. "Sometimes a preggo girl just wants a chat! Lol."
The songstress had taken a couple of months maternity leave to prepare for motherhood, using the time to stock up on cute little outfits for "the little dude", which she posted for her followers to coo over.
Even so boredom was beginning to get the better of her as her bandmate Una Healy told HELLO! Online: "We're missing Frankie of course. I saw her last week and she said she was getting a bit bored which is unsurprising given how busy life usually is as a member of The Saturdays."
"I told her that once her little baby boy arrives she will never, ever say those words ever again and she was happy to hear that!"
Frankie, 24, broke the news of her pregnancy in May, tweeting: "Some big news from me today! Wayne and I are having a baby.
"We are both SO happy and can't wait for his or her arrival!".
It followed the couple's engagement a month earlier after a three-year courtship. The brunette teased fans on the social networking site writing, "Guess what?!!!!" and linking to an image showing her jokingly gasping in shock, a diamond sparkler adorning her finger.
Wayne asked for her hand with a quirky proposal involving her beloved dogs wearing bride and groom outfits.
The new mum won't want for advice. HELLO! Online blogger Una has a little girl called Aoife Belle, aged 19 months, with her husband rugby player Ben Foden. Meanwhile their colleague Rochelle Humes is mother to a five-month-old Alaia-Mai with her man Marvin Humes.
For more about The Saturdays click here to read Una's blog