Abstract
OBJECTIVES. The aim of the prospective nationwide study was (1) to describe rates and causes of infant (incl neonatal) mortality and neonatal morbidity in relation to gestational age groups; (2) to describe the prevalence of congenital anomalies by the EUROCAT subgroups.
METHODS. Data for a neonatal database consisting of 58 variables regarding pregnancy, delivery, neonatal transport, survival, morbidity and treatment particulars were collected prospectively in Estonia in 2007–2008 for all live-born neonates at 22–42 completed gestational weeks (GW) admitted to neonatal or intensive care at Estonian 3rd level hospitals. Additionally, the data of all (n = 351) neonates transferred from local hospitals to children’s hospitals were included. On the basis of the neonatal database, we analysed infant mortality until discharge and compared the data with those of the national death database. Overall birth data were obtained from the national birth register to find representation for each gestational age group in the neonatal database.
RESULTS. The neonatal database includes the data of 4250 newborns (i.e. 13,3% of the total population) born between 22 and 43 completed GW in 2007–2008 in Estonia. Of the newborns 62% were born at 3rd level maternity hospitals. The representation of infants < 32 GW in the neonatal register was 100%; 32–33 GW, 88,5%; 34–36 GW, 60%; term infants (37–41 GW), 9,4% and postterm infants (>42 GW), 11,6%.
Perinatal mortality rate in Estonia was 6,1‰. Early neonatal mortality rate was 2‰, which contributed 40% to overall infant mortality rate (5‰). Of the infant mortality cases 59% occurred during the first hospitalization (range 0–141days), according to the neonatal database. Among them, one third were term infants (death because of congenital anomalies or asphyxia-related conditions) and the remaining infants were born preterm. One third of the deaths occurred after treatment withdrawal consent (in term infants because of congenital anomalies or severe asphyctic brain damage), in preterm infants < 29 GW the main cause of death was grade IV intraventricular hemorrhage grade.
Morbidity is analysed in gestational agebased subgroups, the overall morbidity and prevalence of congenital anomalies are similar to the published results. Possible causes of higher Estonian mortality rates in comparison to EU and Nordic countries are discussed.
CONCLUSION. Data collection to the national birth register is somewhat limited and does not provide enough information for analysis of infant mortality and neonatal morbidity. Collection of population-based enlarged database is necessary for a detailed analysis to further reduction of mortality and improvement of neonatal/child health and to plan health care resources.