OBJECTIVES: to estimate some of the risk factors for low birthweight in Guaratinguetá, a city located in Southeast Brazil, based on records from mothers seeking the vaccination service of the Universal Health Systemin 1998. METHODS: cross-sectional studies with convenience sampling corresponding to 598 mothers interviewed - 28, 9% of the deliveries in the year of 1998. Independent variables were maternal weight gain, number of medical visits, parity, infection of the genital and urinary tract, arterial hypertension, smoking, mother's age and marriage and job status. Logistic regression was used and relative and population attributable risk estimated; significance level was established at p < 0,05. RESULTS: variables with statistical significance present in the final model were maternal age under 20 years old (OR = 2,08) other underweight children (OR = 3,94), weight gain equal or under 10kg (OR = 1,69), arterial hypertension (OR = 2,16) and smoking (OR = 2,43). CONCLUSIONS: the control of these last three factors, that may occur during prenatal care, to the contrary of the other two, may reduce in almost 50% the prevalence of low birthweight.
Infant; Risk factors; Logistic models; Vaccination
