Background: The study was intended to analyse the independent effect of some facets of the socio-economic status of both parents on perinatal, neonatal and post-neonatal mortality in the northern region of Belgium (the Flanders). Method: Perinatal data collected by the Study Centre for Perinatal Epidemiology were linked with socio-economic data collected by the district council. Mothers aged ≥25 years are included in the study. Results: 50796 births were analysed. 452 infants died either before birth or during the first year of life. 52% of the foeto-infantile mortality occurred before birth and 57% of the infant mortality in the first week of life. The educational level was strongly related to foetal ( p <0.001) and, to a lesser degree, to early-neonatal mortality ( p =0.001). Employment did not correlate with any mortality item. Except for foetal mortality, the strongest correlation was always observed for maternal rather than paternal social items. In a logistic regression model, foetal mortality, perinatal mortality and infantile mortality remained strongly correlated with the educational level of the mother. Infant mortality beyond the first week of life was not correlated with any aspect of the social status of the parents. Conclusions: The educational level of the mother is the single most important determinant of infantile mortality in the Flanders representing the totality of hospital births by mothers aged ≥25 years in 1999 in the Flanders