The reality TV star explained that she had a new 'tummy tuck' operation in May in order to reduce stretched skin after her pregnancies.
"I've had four children, which means there was loads of loose skin because my stomach had stretched so much," she told Now.
"No matter how many sit-ups I did, it wouldn't go."
She added: "I got tired of tucking my extra skin in my knickers.
"It was like having an extra toe that shouldn't be there. I had to get it removed."
Kerry Katona recently confirmed that she had split from boyfriend Steve Alce, after they began dating in October 2011.
She has been rumoured to be joining Atomic Kitten for an upcoming reunion of the girl group.