Background: Congenital Heart Defects (CHDs) are the most common structural defects of newborns (5-15 per 1000 live births). Southern Israel population comprises of Jewish population (80%) and Bedouin Arabs (20%), who have a high rate of consanguinity (50-60%) and an abortions rate 2.5 times lower than the Jewish population.
Aims: To assess the CHD epidemiology and the association with maternal characteristics.
Methods: A population-based study of all births during 1991-2011 in Soroka University Medical Center, a tertiary hospital admitting all births in the area (n=247,289) with 6,078 newborns having CHD. To account for the same woman deliveries a general estimating equation models adjusted for gender and ethnicity were used.
Results: The incidence of CHDs was 24.5/1,000 live births, increasing over the last 20 years from 12.32 to 27.64, with a peak incidence in 2005 of 35.1 with majority (58.6 %) observed in Bedouin Arabs. Maternal risk factors included maternal CHD (adjusted odds ratio [aOR] 2.81, p<0.001), CHD in other children (aOR 16.27,p<0.001), maternal age>35 (aOR 1.2,p<0.001), in-vitro fertilization (IVF) (aOR 1.4,p=0.009), recurrent pregnancy loss (aOR 1.18, p<0.001), diabetes mellitus (aOR 1.76,p<0.001) and anemia (aOR 1.16,p<0.001). Defects most associated with CHD in siblings were hypoplastic left ventricle (22.1%), TOF (20.4%) and TGA (19.6%).
Conclusion: The incidence of CHDs has increased over the last 20 years worldwide. Southern Israel has a significantly higher incidence than reported in other countries. Maternal factors associated with CHDs include miscarriages, IVF, diabetes mellitus and anemia, which was previously unreported and could support the use of iron supplements as part of CHD prevention. Furthermore, a strong association was found between CHD in the newborn and maternal and sibling CHD demonstrating a clear familial connection. Genetic studies in this population could help elucidate this relationship and shed light on the genetic and molecular basis of these defects.
