During this fall, the Institute of Medicine is expected to start gathering scientific evidence to support how much weight pregnant women should gain. The current guidelines, which were announced in 1990, recommends that women with low body mass index scores should gain 40 pounds, women with normal scores should gain 25-35 pounds, and obese women should gain 15 pounds. In 2003, around 25% of pregnant women in the U.S gained more than 40 pounds during pregnancy.