Bajo peso al nacer en el municipio de Pelotas, Brasil: Factores de riesgo

Abstract

During 1982, a study was made of all 7 392 hospital births occurring in the municipality of Pelotas, Southern Brazil. This population represents over 99 of all births in the area. The study was carried out in three parts: hospital interviews of all mothers, home visits of a random sample of 15 (1 093) of the new born babies, and checking of birth and death certificates at the local registries. Risk factors which were apparent in the beginning of pregnancy (predictive factors) were identified and their relative importance was studied through multiple regression analysis. The most importnt were: maternal weight at the beginning of pregnancy, height, smoking, the history of a previous low birthweight birth, parity and family income. Further analysis was performed to include those factors concerned with delivery (explanatory variables), such as gestational age and sex of the baby. The most important variable was maternal weight at the end of pregnancy, followed by gestational age. An important finding was the strong positive association between attendance at antenatal clinics and a lower incidence of low birthweight, even after allowing for the possible confounding effects of maternal weight, income, smoking and parity. Most risk factors identified could have been used by health workers to direct the women to the appropriate levels of care