The pregnant model told listeners of her Fubar radio show on Tuesday (24 June) that she isn't too concerned about regaining her pre-baby body, judging by past experience.
Katie is already to mum to sons Harvey, twelve, Junior, nine, and Jett, ten months, along with daughter Princess, six.
Today, Katie said she'd been "quite good" throughout her current pregnancy, after gaining four stone with Jett, who was born in August 2013.
"I think I'm carrying this time like how I did with Harvey and I will definitely snap back," she said.
Discussing the pressure on women to lose their baby weight, she said: "It's so true. Obviously people will watch me and what my body will be like, but I have to be honest, I did ping back small.
"With Junior and Princess I never worked out. With Jett, I bloomed up and never shrunk back [as I got pregnant again a few months later]. Being in this industry, I don't care what people think. If I want to get slim, I will. Every day people are dieting, nobody is the same."
However, she did say: "They say you are what you eat, but if that's true, I should be massive!"
Katie, 36, also spoke about Tamara Ecclestone's weight loss since giving birth to daughter Sophia in March. She was pictured on the beach in her bikini this week.
"Tamara looked brilliant even when she was pregnant," said Katie. "Sometimes she wore these outfits where I thought, 'Where is the bump?!' Looking at her now in a bikini you wouldn't know she's had a child."
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