The former glamour model, author and businesswoman admitted that, because of past experiences, she has vowed never to make the same mistake again.
She told The New Review, available with this weekend's Independent on Sunday, that her decision not to give Kieran any of her rumoured £45 million fortune will "keep them together".
She said: "It's a shame, in a way, because he is lovely, and I want to spoil him, but I've said to him that I've been taken advantage of so bad in the past that unfortunately he's going to get f**k all from me.
"It's what will keep us together."
Katie wed the plasterer and part-time stripper in the Caribbean in January, and announced they were expecting their first baby together just weeks later.
The new baby will be Katie's fourth child. She had eldest son Harvey, 11, with footballer Dwight Yorke, and Junior, 8, and Princess Tiamii, 6, with first husband Peter Andre.
Of her marriage to singer Pete, she says: "When I was married to Pete, I don't know what I was thinking.
"Everything we did was documented, every party, every trip... It's not healthy."
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