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Updated: Jun 8, 2026
Three-dimensional Rendering and Analysis of Immunolabeled, Clarified Human Placental Villous Vascular Networks
Published on: March 29, 2018
Analysis of secondary ultrasound markers in the first trimester before chorionic villus sampling
Francisca S Molina García1, María Paz Carrillo Badillo, Edgar A Zaragoza García
1Fetal Medicine Unit, Obstetrics and Gynecology Service, Virgen de las Nieves University Hospital, Granada, Spain. fsoniamolina@gmail.com
Objective:
To evaluate detection and false-positive rates of the ultrasound markers-nasal bone (NB), ductus venosus (DV) flow and tricuspid regurgitation (TR)-during the first trimester in a population at high genetic risk, and to study the influence of a two-stage screening policy alter previous combined screening on the rate of invasive procedures.
Methods:
A total of 333 chorionic villus samples were obtained in singleton pregnancies. Before biopsy, the ultrasound markers-NB, DV, and TR-were assessed, although the findings were not used to recalculate the previously determined risk for Down syndrome.
Results:
Detection and false-positive rates for Down syndrome were 63.2% and 3.4% for NB, 65% and 3.1% for DV, and 50% and 2.1% for TR. All three markers were normal in 30% [84/277, 95% confidence interval (CI) 25%-36%] of chorionic villus sampling (CVS) cases performed for abnormal findings at the first trimester genetic screen, with 0% (0/20, 95% CI 0%-17%) false-negative rate for Down syndrome.
Conclusion:
Assessment of secondary ultrasound markers is feasible in clinical practice and their use could reduce the number of unnecessary invasive procedures by 30%.
