The "Titanic" star and No. 1 "Yummy Mummy" has two children, Mia, 4, and 20-month-old Joe.
Winslett, who refused to diet after her kids were born, won on the basis of her relaxed, down-to-earth attitude about her figure, Sky News reported.
In second place was the model known only as Jordan, who wore hotpants just weeks after giving birth to her son.
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