Background: Neonatal asphyxia is an important cause of mortality and neurological sequelaes. Objective: Identify maternal, perinatal and neonatal risk factors associated with low Apgar Score (AS). Method: A multivariate analysis using logistic regression model was performed to identify risk factors in a population of 57.241 infants, born between 1997 - 2004, whose information was recollect prospectively in a computer data base. Results: 1.167 newborns had a 1-minute AS £ 3 (2,06%) and 291 presented a 5-minute AS £ 5 (0,51%). The low AS predictors, according to multivariate analysis, were: very low birth weight, prematurity, congenital malformations, low gestational age, placental abruption, 42 - weeks pregnancy, meconium stained amniotic fluid and forceps. Conclusions: Risk factors of low AS are identified in our population, essential for an adequate perinatal care