Predictive value of increased nuchal translucency as a screening test for the detection of fetal chromosomal abnormalities

Abstract

Objective: The study aimed to estimate the incidence of increased nuchal translucency in the first trimester ultrasound scan results (cut-off limit 2.5 mm) and to evaluate the predictive value of increased nuchal translucency as a screening test for the detection of fetal chromosomal abnormalities.

Methods: We used the ultrasound scan results of nuchal translucency evaluation and the results of chromosomal analysis of the invasive prenatal control performed as a result of increased nuchal translucency.

Results: We collected 2183 nuchal translucency ultrasound scans in which we detected 21 embryos with a pathologic value (0.96%). We collected the data of 168 cases of invasive prenatal control due to increased nuchal translucency from which 122 cases were found. A total of 122 cases of pregnant women undergone an invasive prenatal diagnostic method due to increased nuchal translucency, of which 11 fetuses were found with trisomy 21 (Down syndrome) (9%), 3 fetuses with trisomy 13 (Patau syndrome) (2.45%), 3 fetuses with monosomy 45XO (Turner syndrome) (2.45%) and 1 fetus with translocation (0.8%).

Conclusions: The positive predictive value of the increased fetal nuchal translucency as a screening test for the detection of fetal chromosomal abnormalities based on the results of the chromosomal-genetic analysis of the invasive prenatal diagnostic procedures is 14.8%.