London, Sep 9 - Heidi Klum, who is expecting her fourth child, says her legs and butt will 'explode' in her final month of pregnancy.

The supermodel, who raises three children with husband Seal, and is expecting a daughter next month, piles on the extra pounds in the last month of pregnancy, but is not worried about shifting her baby weight.

'The last month is unbelievable, how rapidly your stomach goes. It's huge! The thighs, the butt - everything explodes in the end. It's bizarre,' contactmusic.com quoted her saying.

'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. 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,' she added.