The Institute of Medicine and the National Research Council have issued new guidelines for gestational weight gain as well as recommendations for action and research that call for "a radical change in the care provided to women of childbearing age." For the first time, these guidelines consider the outcomes of both mother and child during and after delivery and the trade-offs between them. The recommendations call for women to begin pregnancy at a healthy weight and to gain within the guidelines, a goal not previously achieved. They also call for individualized preconceptional, prenatal, and postpartum care to help women attain a healthy weight, gain within the guidelines, and return to a healthy weight. Scientific evidence was inadequate to provide specific guidelines by obesity class or to support a public health recommendation to reduce the guidelines below 5-9 kg (11-20 lb) for obese women.