Background: Inequality in adult health increased in Estonia during the transition period after 1991. We examined inequality in infant survival from 1992 to 2002.
Methods: All 132 854 singleton live births reported to the Estonian Medical Birth Registry in 1992-2001 were linked to the Estonian Mortality Database. The effect of mother's education, nationality, marital status, and place of residence on neonatal (0-27 days) and post-neonatal (28-364 days) death was evaluated in logistic regression with adjustments for maternal age, parity, smoking, sex of the infant, birth weight, and gestational age.
Results: Infant mortality decreased substantially. Risk of death in neonatal period was lowest in Tartu, with a decline from 4.9/1000 in infants born in 1992-1996 to 2.1/1000 in those born in 1997-2001. Decline in neonatal mortality in other regions was from 9.2/1000 to 5.1/1000. Persisting regional differences were unexplained by mothers' nationality, education, or marital status, or the infants' length of gestation. Decline in post-neonatal mortality was less marked and although risk differences between different socio-economic groups decreased, mothers' marital status and education in particular remained strongly associated with risk of post-neonatal death [odds ratio for infants born to mothers with basic or lower education compared to university education 3.70 (95% confidence interval 2.34-5.85) in 1992-1996 and 3.56 (2.06-6.14) in 1997-2001].
Conclusions: Infant survival improved appreciably in Estonia after 1991 and risk differences between social groups decreased. The improvements were not accompanied by reduction in the strength of the effects of social characteristics on infant death measured as risk ratios.