Early neonatal deaths associated with perinatal asphyxia in infants ≥2500g in Brazil.

OBJECTIVE: To assess the annual burden of early neonatal deaths associated with perinatal asphyxia in infants weighing ≥2500g in Brazil from 2005 to 2010.

METHODS: The population study enrolled all live births of infants with birth weight ≥2500g and without malformations who died up to six days after birth with perinatal asphyxia, defined as intrauterine hypoxia, asphyxia at birth, or meconium aspiration syndrome. The cause of death was written in any field of the death certificate, according to International Classification of Diseases, 10th Revision (P20.0, P21.0, and P24.0). An active search was performed in 27 Brazilian federative units. The chi-squared test for trend was applied to analyze early neonatal mortality ratios associated with perinatal asphyxia by study year.

RESULTS: A total of 10,675 infants weighing ≥2500g without malformations died within six days after birth with perinatal asphyxia. Deaths occurred in the first 24h after birth in 71% of the infants. Meconium aspiration syndrome was reported in 4076 (38%) of these deaths. The asphyxia-specific early neonatal mortality ratio decreased from 0.81 in 2005 to 0.65 per 1000 live births in 2010 in Brazil (p<0.001); the meconium aspiration syndrome-specific early neonatal mortality ratio remained between 0.20 and 0.29 per 1000 live births during the study period.

CONCLUSIONS: Despite the decreasing rates in Brazil from 2005 to 2010, early neonatal mortality rates associated with perinatal asphyxia in infants in the better spectrum of birth weight and without congenital malformations are still high, and meconium aspiration syndrome plays a major role.