But in a series of messages she posted online, the 35-year-old model told her fans: "Sorry to say me and kieran are divorcing."
Airing her upset to the world via Twitter, she wrote: "No human being deserves this especially being 6 months pregnant."
Another message added: "Worse pain in the world."
A spokeswoman for Price did not wish to comment when asked about the messages posted on Price's account, which also made allegations about the reasons for the breakdown of her marriage.
It is the latest chapter in the colourful world of Katie who has previously been married to singer and TV personality Peter Andre and the 'Celebrity Big Brother' contestant and cage-fighter Alex Reid.
She and Reid separated in January 2011 after being married for less than a year.
She and Hayler had their first child together, Jett, in August last year.
She also has two other children, Junior and Princess, from her four-year marriage to Andre and a son Harvey from her brief relationship with footballer Dwight Yorke.
In a magazine interview this week she had told how she learned she was expecting on returning from a holiday in Cape Verde.
She told Now magazine that they thought she was just a few weeks pregnant when the couple went for a scan the following day.
"We were lying there... then this picture flashed up on the screen and we saw this enormous baby," she said.
"I was in shock, he was in shock - even the doctor was in shock. I was still in size 6-8 trousers… None of us could actually believe it."
Katie Price's Past Men...
Frank Lampard(01 of12)
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Katie says to have never gone "all the way" with Frank (how charming), but claims the two had a fling earlier in their respective careers.In 2009 she even told Glamour: "There's actually quite a few little footies I'd do. I'd probably go back to Frank Lampard, finish what I started."Poetry in motion (credit:Getty Images)
Teddy Sheringham(02 of12)
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Frank isn't the only footballer Katie's been with in the past, as her childhood sweetheart revealed in an interview in 2011 that he was devastated when Katie cheated on him with Teddy Sheringham.He later dated Katie's friend Danielle Lloyd. (credit:Getty Images)
Warren Furman(03 of12)
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Kelly Brook isn't the only star with a taste for 'Gladiators', as Katie dated Warren Furman, better known as 'Ace' on the 90s Saturday night entertainment show, for two years until they split in 1998.Warren later revealed that he thinks Katie enjoys "grinding men down" emotionally. (credit:Rex/ITV)
Gareth Gates(04 of12)
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When Katie revealed to the press that she'd had a fling with 'Pop Idol' runner-up Gareth Gates - who was 17-years-old at the time - he denied the claims, though later admitted that he had been with Katie for around "three or four months".During an appearance on 'The Big Reunion' he claimed she "ruined" his career, though in her defense we don't think it was Katie who forced him to do a charity duet with The Kumars/ (credit:Getty Images)
Ralf Schumacher(05 of12)
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Racing driver Ralf denies ever having been involved with Katie, though she says they had a three-year affair. (credit:Getty Images)
Dwight Yorke(06 of12)
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Katie dated footballer Dwight Yorke, and he later fathered her first child Harvey, though the former glamour model says they have no relationship and as recently as 2013 claimed Dwight was "missing out" by not seeing his son. (credit:Getty Images)
Danny Cipriani(07 of12)
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Kelly Brook was furious when Katie revealed in her book 'Love, Lipstick And Lies' in 2013 that she had briefly dated her then-boyfriend Danny Cipriani in 2011, dumping him after she found him in bed with another woman. (credit:Getty Images)
Dane Bowers(08 of12)
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Katie was also lucky enough to date former Another Level singer Dane Bowers. Their relationship is probably most famous because of the much-shared sex tape that stemmed from it, though we'd honestly rather not think about that if you don't mind... (credit:Getty Images)
Peter Andre(09 of12)
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Probably the most famous of Katie's relationships, the loved-up pair met on 'I'm A Celebrity...Get Me Out Of Here!' and after marrying in 2005 became ITV2's equivalent of the Royal Couple. Unfortunately, they ultimately divorced just days before their fourth wedding anniversary, and their relationship since has been frosty to say the least. (credit:Getty Images)
Alex Reid(10 of12)
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Not long after splitting from Peter, Katie began dating wild child cage-fighter and occasional actor Alex Reid, marrying him just days after he was crowned winner of 'Celebrity Big Brother'.They ultimately divorced, with Katie branding their marriage a "rebound" in 2014. (credit:Getty Images)
Leandro Penna(11 of12)
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Despite the language barrier between them, Katie announced in April 2012 that she was engaged to Argentinian model Leandro Penna, who she'd met at the Oscars, of all places.Just six months later Katie revealed they'd "mutually" decided to end their engagement. (credit:Getty Images)
Kieran Hayler(12 of12)
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Which brings us back to Kieran, a builder and occasional stripper who Katie married in a private ceremony in the Caribbean back in January 2013.Shortly after giving birth to his son Jett - Katie's fourth child - they unknowingly conceived another baby, with Katie not realising she was expecting until six months into her pregnancy. Around this time, tweets were posted on Katie's Twitter account announcing she was divorcing him. Next! (credit:Getty Images)