Mortality on the first day of life: trends, causes of death and avoidability in eight Brazilian Federative Units, between 2010 and 2015.

Objective: to calculate mortality rates on the first day of life from 2010 to 2015 in eight Brazilian Federative Units providing better quality information, to assess associated factors and to classify deaths by underlying causes and avoidability.

Methods: this was a descriptive study; mortality rates were compared according to maternal and child characteristics; avoidability analysis used the 'Brazilian list of avoidable causes of death'.

Results: 21.6% (n=20,791) of all infant deaths occurred on the first day of life; the mortality rate reduced from 2.7 to 2.3 deaths/1,000 live births; rates were higher in live births with low birthweight and preterm births, and among babies born to mothers with no schooling; main causes of death were respiratory distress syndrome (8.9%) and extreme immaturity (5.2%); 66.3% of causes of death were avoidable.

Conclusion: 2/3 of deaths on the first day of life could have been avoided with adequate care for women during pregnancy and delivery and adequate care for live births.