Using medical birth registries in the Kola Peninsula for birth defects surveillance and investigation of their risk factors

Abstract

Medical birth registries are valuable sources of information about maternal and newborn’s health. In North-West Russia the registries were initiated in 1997 in the city of Monchegorsk and for all of Murmansk County in 2005. In this thesis we demonstrated the effectiveness of these data sources for surveillance of birth defects with the following objectives: (i) estimated changes in prevalence of birth defects during forty-year period, (ii) identified effect of ultrasound screening during pregnancy, (iii) defined factors which associated with urinary malformations. Our study with data from 1973 to 2011 showed that the prevalence of birth defects demonstrated a two-fold increase, and the initiation of prenatal ultrasound screening was the most likely reason for such changes. The initiation of the screening was also the main reason for the decline in perinatal mortality among newborns with birth defects, primary due to prenatal detection of severe malformations with subsequent terminations of such pregnancies. Moreover, the mothers who had undergone at least one ultrasound examination during pregnancy had a decreased risk of having a newborn die during the first week of life. Congenital anomalies of the kidney and the urinary tract showed the highest increase in prevalence during 1973-2011. During pregnancy, use of medications, infections, diabetes were associated with increased risk of this group of anomalies, as was conception during summer. The medical birth registries in Murmansk County constitute powerful sources for birth defects surveillance and the investigation of risk factors. Combination of these registries with existed system of monitoring birth defects and mandatory registration of pregnancy terminations can increase their research potential.