Jessica Simpson 'Determined' and 'Excited' to Drop Baby Weight

The pressure is on for Jessica Simpson!

Now that the "Fashion Star" mentor has given birth to her daughter, Maxwell Drew, it's time to start prepping for her other new baby: a new $4 million deal with Weight Watchers!

"As soon as Jessica heals from the C-section, she is extremely determined to get back in the gym and work out," a confidant tells Us Weekly. "She wants to show the world and is excited to do it."

PHOTOS: Jessica Simpson's chic maternity style

Since announcing on Oct. 31 that she and her fiance, Eric Johnson, were expecting their first child, Simpson, 31, has been under serious scrutiny over her pregnancy weight gain.

PHOTOS: Impressive post-baby bodies

But now, the 5-foot-3 star, who admitted to weighing 170 pounds when she posed nude and pregnant for the April issue of Elle, needs to do a serious post-baby slim down over the next few months to fulfill her contractual obligations. After all, her notable junk-food pregnancy cravings included Laffy Taffy, buttered Pop Tarts, and Kraft macaroni & cheese with Lawry's seasoning salt.

PHOTOS: Jessica Simpson's weight ups and downs

A source familiar with the Weight Watchers negotiations tells Us the stakes are high, since it's literally no pain, no gain.

"She'll have to meet the weight-loss goals for the deal to go through," says the source. "She hasn't chosen a trainer yet. In fact, she hasn't even thought about working out for a year. But if she wants this, she'll need to work out a good five times a week."

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