Abstract
Background
Anencephaly is a lethal anomaly of the central nervous system from the group of neural tube defects. The main goal of our study was to evaluate the incidence of anencephaly (and its possible trends) during the 53 years period.
Methods
For this study, we used data from the National Registry of Congenital Anomalies of the Czech Republic. We analysed the incidence of anencephaly in births and in prenatally diagnosed cases during the 1964-2016 period. We also evaluated maternal age in these cases. The statistical analysis was performed by Poisson regression and Fisher's exact test.
Results
During the study period there were 6 891 062 children born in the Czech Republic. Among those, 1232 children were born with anencephaly. Another 966 cases of anencephaly were diagnosed during prenatal diagnosis and these pregnancies were electively terminated, the total number of anencephaly cases was 2198. The total incidence of anencephaly significantly decreased during the study period (p = 0.0136). The incidence in births decreased significantly as well (p < 0.001). We found statistically higher incidence of anencephaly in elder mothers (42 years and over).
Conclusions
Gradual implementation of ultrasound prenatal diagnostics started in the 80s of the last century and lead to a very significant decrease in the incidence of anencephaly cases in births. Additionally, the total incidence of anencephaly decreased significantly as well.
Key messages
Incidence of anencephaly in births decreased rapidly with gradual implementation of population wide ultrasound screening.