Star: Late into her pregnancy, at just 5'5", Britney Spears has gone from an estimated 119 lbs. to about 170 lbs. - a 51-pound increase, larger than the average pregnancy weight gain is 25 to 35 lbs. But Spears seems to be embracing her new, large self, saying, "I think I'll always have a weight problem." Fitness expert Michael George still has hopes the singer can slim down after giving birth later this month. "Britney should follow a diet of 40% carbohydrates, 30% protein and 30% fat," George advised. "She needs to work up to 45 minutes of cardio six days a week, and some high-intensity strength training three to four times a week."