The former glamour model, 36, looked nervous when she arrived in the famous house on Friday night (16 January) and soon told her fellow co-stars about her marriage woes - and botched surgery.
Outspoken Katie was the centre of attention after arriving in the house and was quick to tell her new friends about her recent breast reduction gone wrong.
She told a shocked Alicia Douvall that she has a hole from where her breast implant removal surgery has gone wrong.
The mum-of-five also revealed that she was set for surgery next week, but decided to enter the CBB house instead.
She revealed: "They were going to take them out on Monday. That's how bad it's gone under there, it's a hole, my implant was hanging out on New Year's Day.
"But it hasn't stopped me coming in, because I'm not running around."
She also mentioned that she currently has restricted movement in her arm because of the complications.
In December, Katie had surgery to reduce her 34FF breasts and a doctor will be on standby the entire time she is in the house.
Katie also told housemates, including Katie Hopkins and Calum Best, about the moment she discovered her husband Kieran Hayler cheating with her best friend of 20 years Jane Pountney.
In a foul-mouthed rant, she blasted: "I knew he had a problem, he must have done, because they're f*****g mingers."
She told her appalled audience that, while pregnant, she had seen Kieran kissing Jane on a couples' holiday to Cape Verde.
She fumed: "I got her f*****g head, f*****g pulled her off the sun bed, f*****g whacking her."
Katie then revealed that Jane and Kieran had been "s******g for 10 months".
The horse-mad reality TV star also shocked viewers when she appeared to be getting along with Katie Hopkins!
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