The evolution of prenatal diagnosis in the early detection of congenital anomalies: data from 1997 to 2016

Abstract publicado em: European Journal of Medical Genetics. 2018;61(9):572. https://doi.org/10.1016/j.ejmg.2018.06.071BACKGROUND: The Portuguese prenatal surveillance programme advise ultrasound screenings, in the first trimester of pregnancy in combination with the blood test, and between 20 - 22 weeks of pregnancy. Other tests are offered in pregnancies with an increased risk. The aim of this study is to assess the evolution of prenatal diagnosis in the detection of congenital anomalies (CA). METHODS: A cross sectional study was implemented using data collected between 1997 - 2016 by the Portuguese registry of CA (RENAC) a population base registry that follow EUROCAT guidelines. A case was defined with at least one CA potentially detectible by prenatal diagnosis. Descriptive analysis was performed using absolute and relative frequencies and bivariate analysis was conducted using chi-square statistics. RESULTS: The analysis included 13566 cases reported with at least one CA. There was an statistically significant increase in the detection of CA through prenatal diagnosis compared to detection at birth or after birth (p<0.001). In addition, there was an increase of cases detected during pregnancy from 52.1% (1997-1999) to 62.9% (2009-2016) especially in cases detected before 14 weeks (7.9% to 28.9%). Comparing the same periods of time the results also show a range of ultrasound screening from 27% to 55.8% and a decrease in invasive tests from 18.9% to 3%. This tendency was statistically significant (p