OBJECTIVES: to assess the performance of various anthropometric methods for the evaulation of the nutritional status of pregnant women as a means of predicting low birth weight (LBW). METHODS: a descriptive cross-cutting study carried out among 433 pregnant women (>20 years) attending a Public Maternity Hospital in Rio de Janeiro, Brazil. The adequacy of the weight gain at the end of the pregnancy was evaluated in accordance with the proposals of the Institute of Medicine and the Brazilian Ministry of Health. The sensitivity, specificity and accuracy of the adequacy of weight gain at the end of the pregnancy or nutritional state of mother as a predictor of low birth weight were calculated. RESULTS: the sensitivity of the various methods varied from 63.1% to 68.4% and the specificity from 71.2% to 75.1%. The adapted Institute of Medicine proposal drawn up by the Brazilian Ministry of Health, according to the classification of the pre-delivery nutritional status of the mother according to the World Health Organization cutoff points showed itself to be the most accurate (74.5%), this being the most adequate method for nutritional triage for reason of its association with low birth weight (OR=4.10; 95%CI=1.53-10.92). CONCLUSIONS: the best proposals for this population are those of the Institute of Medicine and the Brazilian Ministry of Health. Further studies aiming to ascertain the most appropriate methods of anthropometric evaluation for different populations should be encouraged.
Pregnancy; Anthropometry; Weight gain; Infant; Low birth weight
