Isla Fisher doesn't weigh herself regularly because she wants to set a good example for her daughters.

The Australian actress - who has two daughters Olive, five, and Elula, two, with her 41-year-old husband Sacha Baron Cohen - relies on yoga to keep her figure trim but tries not to be too strict with her diet as she wants her daughters to grow up with a positive body image.

She told the new issue of Fitness magazine that she was happy to gain weight for her role in 'The Great Gatsby', saying: ''I gained 15 pounds. It mainly manifested itself in my boobs, which was very exciting. Sadly, that's gone now.''

The 37-year-old beauty also revealed that she didn't put any pressure on herself during either of her pregnancies.

She said: ''I gained 65 pounds with my first baby and 70 with my second. I mostly ate supersize bowls of white pasta with loads of butter and cheese, late night cornflakes, Haagen-Dazs ice-cream and scones with jam and cream.''

She claims she got her back to her pre-pregnancy weight with the help of a personal trainer and breastfeeding but insisted concerned if stomach is never completely flat again.

She said: ''Even though it will never be flat again, it's still my favourite because it reminds me f my greatest achievement: my babies.''