Brazil is the world's largest consumer of pesticides. Epidemiological studies have shown an association between maternal exposure to pesticides and adverse pregnancy events. An ecological study was conducted to investigate potential relations between per capita pesticide consumption and adverse events in live born infants in micro-regions in the South of Brazil (1996-2000). The data were obtained from the Brazilian Institute of Geography and Statistics (IBGE) and the Health Information Department of the Unified National Health System (DATASUS). Micro-regions were grouped into quartiles of pesticide consumption, and prevalence ratios (PR) were calculated. Linear trend p-values were obtained with the chi-square test. Premature birth (gestational age < 22 weeks) and low 1 and 5-minute Apgar score (< 8) in both boys and girls showed a significantly higher PR in the upper quartile of pesticide consumption. No significant differences were observed for low birth weight. The findings suggest that prenatal pesticide exposure is a risk factor for adverse pregnancy events such as premature birth and inadequate maturation.