RESUMO
With a view to evaluating the effect of anemia and maternal undernourishment on birth weight, a sample of 691 pregnant women, from an assistential maternity hospital, in S. Paulo, Brazil, were studied at delivery. Anemia was found in 29.1% and undernourishment in 17.2% of the women, though no association was detected between these nutritional deficiencies. Neither was any association detected between institutional ante-natal care and anemia or undernourishment. Among single newborns the incidence of low birth weight (LBW) was of 12.9%. LBW was observed in 23.6% of children born to women who came to the end of their pregnancy with a low weight for height ratios while among adequate weight for height women the percentage was 10.8. Children of women who remained undernourished throughout their pregnancy had a relative risk of being born with LBW 2.8 times greater than the children of those who recovered normal weight by the end of their pregnancy. Our results emphasize the need for implementation of nutritional status control activities in programs of ante-natal care.