Decreasing perinatal mortality in The Netherlands, 2000-2006: a record linkage study.

BACKGROUND The European PERISTAT-1 study showed that, in 1999, perinatal mortality, especially fetal mortality, was substantially higher in The Netherlands than in other European countries. The aim of this study was to analyse the recent trend in Dutch perinatal mortality and the influence of risk factors. METHODS A nationwide retrospective cohort study of 1,246,440 singleton births in 2000-2006 in The Netherlands. The source data were available from three linked registries: the midwifery registry, the obstetrics registry and the neonatology/paediatrics registry. The outcome measure was perinatal mortality (fetal and early neonatal mortality). The trend was studied with and without risk adjustment. Five clinical distinct groups with different perinatal mortality risks were used to gain further insight. RESULTS Perinatal mortality among singletons declined from 10.5 to 9.1 per 1000 total births in the period 2000-2006. This trend remained significant after full adjustment (odds ratio 0.97; 95% CI 0.96 to 0.98) and was present in both fetal and neonatal mortality. The decline was most prominent among births complicated by congenital anomalies, among premature births (32.0-36.6 weeks) and among term births. Home births showed the lowest mortality risk. CONCLUSIONS Dutch perinatal mortality declined steadily over this period, which could not be explained by changes in known risk factors including high maternal age and non-western ethnicity. The decline was present in all risk groups except in very premature births. The mortality level is still high compared with European standards.