Weight gain advice showed a notable shift for white married mothers during the 1980s, with a large decline in reported advice of less than 22 pounds concomitant with a substantial increase in reported advice of 28 pounds or more. For black married mothers, there was little change in reported advice, except in the proportion of mothers who said they were advised to gain at least 35 pounds, which increased from 2 to 11%. It should be noted that it is not possible to corroborate the information on weight gain advice reported by mothers in 1980 or 1988 because of the lack of similar information from the providers of prenatal care. However, for the 1996 NMIHS, the feasibility of collecting such information from prenatal care providers will be examined. In view of the strong, positive relationship between maternal weight gain and birth weight, optimum weight gain advice for white and black mothers is critical. A recent nationwide survey of practicing dieticians found that 26% of the pregnant mothers they counseled believed that one shouldn't gain more than 20 pounds during pregnancy and that obese women didn't need to gain any weight at all. These beliefs were often culturally transmitted. Although only 12% of white mothers reported advice that did not meet the minimum standard in effect in 1988 and 19% reported advice that did not meet the minimum 1990 IOM guideline for their weight and height, a significantly higher proportion of black mothers reported advice of less than 22 pounds (33%) or the IOM minimum (34%). The far more frequent inappropriate advice reported by black than white mothers cannot be explained by differences in body mass index, age, education, parity, marital status, or site of care. Nevertheless, compliance with advice was almost the same for black and white mothers: More than 70% gained at least 22 pounds when this was the reported weight gain advice. It is thus entirely feasible that more appropriate advice for black women will result in significantly higher weight gains and improvement in infant birth weight and health.