Naomi Watts’ trim post-pregnancy figure is all down to “solid underwear”

Naomi Watts’ trim post-pregnancy figure is all down to “solid underwear”.

The 39-year-old actress – who gave birth to her first son Alexander Pete with partner Liev Schreiber less than three months ago – admitted appearances can be deceiving and her toned physique was not all down to hard work in the gym.

When asked what her secret was, she joked to People magazine: “I’ve got a lot of solid undergarments!”

Naomi – who looked stunning in a figure-hugging black dress at a London Calvin Klein event on Monday (15.10.07) – said the right outfit can give the illusion of a svelte figure.

She said: “Good classic lines can also help cheer up an out of shape body.”

The ‘King Kong’ star hosted the launch of the fashion house’s spring/summer 2008 collection in a basement of the University of Westminster where she mingled with guests including Bianca Jagger and Mary-Kate Olsen.

Naomi – who will attend the premiere of her new movie ‘Eastern Promises’ which opens The Times BFI 51st London Film Festival tonight (17.10.07) – also gushed about the joys of motherhood, saying: “I love it! Love it!”