Retrospective analysis of live birth prevalence of children with Down syndrome in Denizli, Turkey.

Down syndrome (DS) is the most frequent chromosome abnormality among live births. Its prevalence increases with maternal age, and can be diagnosed by antenatal screening. We examined prevalence variations of DS in Denizli, Turkey, through a retrospective study. Sixteen years of survey data were retrieved from the two main state hospital registries from records between 1994 and 2010. We identified 113 DS live births in Denizli for 16 years. The prevalence of DS was 9.07 per 10,000 live births before the year 2000 and 9.90 after 2000. The prevalence did not change significantly. The population in Turkey is still young; the fertility rate is high in women under 35 years old and prenatal screening programs are extensively applied; for these reasons, the prevalence of DS has remained stable during these 16 years.