The ‘Strictly Come Dancing’ professional revealed the news to her ‘CBB’ housemates during a conversation on Thursday.
After gathering them in the kitchen, she explained: “There was something that happened in my life, before I came into the house over Christmas… and I didn’t know how to deal with that, and obviously I thought ‘it’s very private news’.
“But because we’re living as one family now, and everybody needs to support one another, it happened to be that I found out that my boyfriend and I are going to have a little one.”
Kristina’s news was obviously met with great jubilation from her housemates, with Danniella Westbrook and Megan McKenna both rushing to hug the expectant mum.
After admitting that whether or not to share her news with the group - and the British public! - had been “playing on her mind”, she added that she was “almost three months” along in her pregnancy.
A spokesperson for Kristina has revealed: "Kristina and Ben were surprised and delighted to find out that she was pregnant shortly before she entered the 'Big Brother' house. Kristina is well and looking forward to being a mum."
Her announcement marks the first time that a pregnant star has ever appeared on ‘CBB’.
In the outside world, Kristina is dating former rugby player Ben Cohen, who she was previously partnered with during his time on ‘Strictly’ in 2013.
Ben is already a father to twin girls with his estranged wife, Abby, while this will be Kristina’s first child.
It was reported shortly before it was confirmed that Kristina was heading into the ‘CBB’ house that the most recent series of ‘Strictly’ would be her last, after seven years competing on the BBC show.
Meanwhile, inside the house, she is one of three housemates currently facing Friday night’s first live eviction, alongside former UKIP member and Winston McKenzie and Nancy Dell’Olio.