Let the great slimdown begin!

Over a month after giving birth to daughter Maxwell Drew, Jessica Simpson was photographed out and about for the first time in Hollywood. Sitting in the passenger seat of a car alongside her personal assitant, the 31-year-old fashion designer's mission wasn't a Frappucino run or a shopping spree. Smiling in a black top and oversized shades, the star was en route to the private gym of celeb trainer Harley Pasternak, who has worked with the likes of Halle Berry, Hilary Duff and many others.

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Pasternak is the perfect coach to help Simpson with her admittedly daunting task. The 5-foot-3 star admitted to weighing 170 pounds when she posed nude and pregnant for the April issue of ELLE magazine -- and now, she's looking to fulfill a $4 million deal with Weight Watchers to shed that weight within a year.

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"As soon as Jessica heals from the C-section, she is extremely determined to get back in the gym and work out," a confidante told Us Weekly shortly after Maxwell's birth. (Maxwell, Simpson's first child with fiance Eric Johnson, weighed 9 lbs 13 oz at birth.)

"She hasn't even thought about working out for a year!" the source continued last month. But if she wants this, she'll need to work out a good five days a week."

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And in her third trimester, Simpson was already beginning to worry about the impending challenge. "She was clearly nervous about how she'd bounce back to normal," another friend told Us.

This article originally appeared on Usmagazine.com: FIRST PIC: Jessica Simpson Steps Out After Giving Birth to Visit Personal Trainer