Fatores contextuais e individuais associados ao baixo peso ao nascer no estado do Rio de Janeiro, 2000-2005

Abstract

Low birth weight (LBW) is a major public health problem worldwide, although more pronounced in less developed areas. LBW children are at greater risk of morbidity and mortality during the first year of life, and those who survive are most at risk of developing sequela. In this study, individual and contextual factors associated with low birth weight were identified based on information on births in the state of Rio de Janeiro from 2000 to 2005. A multilevel logistic model with two levels, municipalities and mothers, was used. The results showed a downward trend in the proportion of low birth weight in the state. On average, each year, the chance of a low birth weight declined approximately 2%. GNP per capita was also associated with low birth weight. Increases of R$ 5,000.00 in annual GNP reduced the chance of a low birth weight by 2%. Adolescents or women aged 40 years or more, as well as single women and widows, were more likely to have a child with low birth weight. The chance of having a child with low birth weight decreased as mother's education increased, but with little variation in the categories above three years of study. The type of hospital emerged as a strong predictor of low birth weight, with increased probability of having a child with LBW among women whose deliveries were performed in public hospitals. Emphasis must be given to the effect that the number of pre-natal consultations exerted on LBW. The chance of a child whose mother had at least seven visits during prenatal care, low birth weight was 44% lower than that observed among mothers who had up to three visits. The variance of the random component estimated by the multilevel model indicates that there is significant variation in the low-weight at the municipal level, not explained by variables included in the analysis. Future studies should seek to identify these factors. Public policies should be implemented, focusing not only on reducing the prevalence of low birth weight, but also on monitoring these children, in order to reduce the chance that a child has sequelae or decrease the damage they caused