Heidi KlumHeidi at a TV screening this weekPregnant Victoria's Secret model Heidi Klum admits her thighs and "butt" have rapidly expanded in recent weeks.

"The last month is unbelievable, how rapidly your stomach goes.

"It's huge," the 36-year-old model told Page Six.

She said: "The thighs, the butt - everything explodes in the end."

Despite her weight "explosion," Heidi isn't worried about her model bod.

She went on: "Just as it's a miracle that you can grow a human being in your belly, it's a miracle that your body goes back to normal again."

Heidi, who's nearing the end of her fourth pregnancy, added: "I don't think you ever get back to exactly the way you were, but you do get close.

"And I'm happy with that. Especially when you see your kid for the first time."

Check out some mums who have definitely got back their tums, post-pregnancy....