The difference in pulling force, from a physics standpoint, is negligible. Had she had a breast reduction, weight would have been removed and then it would be reasonable to conclude it was a medical reason. Torque increases as the mass moves farther from a supported position. Therefore, firming the breast, results in increased torque as less mass is supported, by resting against the body. Only removal of mass, will offset the increased torque. I was being generous, when I said the difference was negligible.