Hilary Duff: Pilates Workout Woman!

Hilary Duff holds on to her scarf as she exits her pilates class on Friday (September 20) in Toluca Lake, Calif.

The 24-year-old actress and soon-to-be mama, who after class hopped in her car and drove away, hid her baby bump under a baggy white t-shirt!

PHOTOS: Check out the latest pics of Hilary Duff

Earlier this week, Hil celebrated her birthday! To kick off the day, she went out to lunch with her older sister Haylie, and even got serenaded by the paparazzi!

10+ pictures inside of Hilary Duff leaving a pilates class in Toluca Lake…