Race may also affect pregnancy weight changes. African American women consistently gain less weight than white women during pregnancy.However, they are generally no different from white women in terms of falling above, at, or below IOM guidelines.Age also affects weight gain during pregnancy; younger women gain more weight than older women, but this effect may be due to high weight gain during growth in adolescent women.Primiparity is also associated with larger weight gains during pregnancy. Abrams and Parker found that weight gains of women with parity of 0, 1, or ≥2 were 34.0, 33.2, and 31.5 lbs, respectively. In another study, 34% of primiparous women exceeded the 1990 IOM guidelines; only 16% of multiparous women exceeded the guidelines.