Kim Kardashian has hired trainer Tracy Anderson to help her stay healthy and fit during her pregnancy. Anderson, who has worked with Gwyneth Paltrow and Madonna, tells us Kim “is just so humbled but thrilled with this news [of being pregnant].” At HBO’s “Girls” premiere screening Wednesday, Anderson said Kim “wants her body to grow and expand. I don’t care if she gains 40 or 70 pounds.” The reality star is the queen of product endorsements, but Anderson says: Be careful. Celebs’ promotion of a weight-loss product is a responsibility “so big, there can’t be or shouldn’t be a price tag to it.” Maybe she’s forgotten the Kardashians have been pushing a weight-loss supplement for some time.