Accuracy of first‐trimester combined test in screening for trisomies 21, 18 and 13

• DOI: 10.1002/uog.17283
• Publication Date: 2016-08-23T07:32:47Z
• Authors: M. Santorum; D. Wright; A. Syngelaki; N. Karagioti; K. H. Nicolaides
• Keywords: Adult; Chromosomes, Human, Pair 13; Reproducibility of Results; Trisomy; Heart Rate, Fetal; Ultrasonography, Prenatal; 3. Good health; Pregnancy Trimester, First; 03 medical and health sciences; 0302 clinical medicine; Predictive Value of Tests; Pregnancy; Humans; Chorionic Gonadotropin, beta Subunit, Human; Female; Prospective Studies; Down Syndrome; Chromosomes, Human, Pair 18; Nuchal Translucency Measurement; Maternal Age

To examine the diagnostic accuracy of a previously developed model for first-trimester combined test in screening trisomies 21, 18 and 13.This was prospective validation study 13 by assessment combination maternal age, fetal nuchal translucency, heart rate serum free β-human chorionic gonadotropin (β-hCG) pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 6 weeks' gestation 108 982 singleton pregnancies undergoing routine care three maternity hospitals. A published algorithm used calculate patient-specific risks trisomy each patient. The detection (DR) false-positive (FPR) estimated risk cut-offs from 1 2 1000 were determined. proportions detected compared their expected values different groups.In population, there 112 (99.2%) cases with normal karyotype or birth phenotypically neonate 870 (0.8%) abnormal karyotype, including 21 (n = 432), 166), 56), monosomy X 63), triploidy 35) other aneuploidy 118). screen-positive rates, standardized according age distribution England Wales 2011, fetuses compatible those predicted previous model; cut-off 100, FPR about 4% DRs 90%, 97% 92%, respectively. There evidence that overestimated risk. This could, some degree, reflect under-ascertainment ending miscarriage stillbirth.In study, 92% 13, respectively, as well > 95% triploidies 50% chromosomal abnormalities, 4%. Copyright © 2016 ISUOG. Published John Wiley & Sons Ltd.