Objectives: The objective of the paper is the suitability assessment of screening for Trisomy 18 and 13 on the basis of nuchal translucency (NT) measurement, Fetal Heart Rate (FHR), double test, quantitative [Ductus Venosus (DV) Pulsatility Index for Veins (PIV)] and qualitative (the A-wave assessment) blood flow evaluation in the DV.
Material and methods: The study was performed in 7296 singleton pregnancies. In each fetus NT, FHR, DV-PIV were examined. Double test from maternal blood was examined. These ultrasound and biochemical factors were in combined screening investigated. Additional doppler ultrasound markers such as abnormal a-wave in Ductus Venosus and Pusatility Index for Veins of Ductus Venosus were and their impact on Trisomies 18 and 13 screening were examined.
Results: Two groups of patients were compared - with chromosomal normal and chromosomal abnormalities - Trisomy 18 and 13. Detection Rate of Trisomies 18 and 13 at the risk cutoff 1/300 using combined screening was 90.2% and FPR was 6%. Detection Rates of examined chromosomal abnormalities using contingent screening were: 92.1% using DV abnormal a-wave and 94.84% using DV-PIV. FPR's for booths parameters 5.8% and 5.4% respectively.
Conclusions: Quantitative analysis of the flow - assessment of DV-PIV in the first trimester significantly influences the improvement of screening values focusing on Trisomy 18 and 13 detection.
Keywords: Combined test trisomy 18 trisomy 13; ductus venosus pulsatility index for veins; first trimester nuchal translucency thickness; pregnancy-associated plasma protein A; serum free β-hcg.