Extended First-Trimester Screening Using Multiple Sonographic Markers and Maternal Serum Biochemistry: A Five-Year Prospective Study

Abstract

Objective: To examine the performance of first-trimester screening test combining several fetal sonographic and maternal biochemical markers for major aneuploidy in a Chinese population. Methods: This was a prospective study performed over 5 years between January 2005 and December 2010 in Taiwan, with 20,586 cases that had a combination of a variety of sonographic markers and maternal serological β-human chorionic gonadotropin and pregnancy-associated plasma protein-A levels assessed at first trimester screening between 11⁺⁰ and 13⁺⁶ weeks of gestation. The risk of aneuploidy was calculated using algorithm software developed by Fetal Medicine Foundation, London. Fetal karyotyping was performed when the prenatal screening showed a risk of 1/300 or higher. All cases were followed for fetal outcome. Results: The study population was divided into four groups according to the screening strategy performed. The combination of maternal serological biochemistry and nuchal translucency measurement had a 66.7% detection rate of trisomy 21. Addition of nasal bone status increased the detection rate of trisomy 21 to 88.2%. Inclusion of tricuspid regurgitation flow showed an 87.5% detection rate of trisomy 21. Further inclusion of ductus venosus flow increased the detection rate of trisomy 21 to 100%. Incorporating more markers greatly increased the detection rate and decreased the false-positive rate (FPR). Conclusion: Extension of first-trimester screening to include more sonographic markers greatly increased the sensitivity and decreased FPR for detection of chromosomal abnormalities. Such screening strategy is effective in clinical practice for the Chinese ethnic population.

First trimester combined screening for fetal aneuploidies enhanced with additional ultrasound markers: an 8-year prospective study

“…However, we failed to reach the excellent 100% detection rates obtained by Hsiao et al [14] or Ghaffari et al [15] at lower FPRs of 2.4% or 3.4%, respectively.…”

“…Using an ultrasound only based protocol, with NT and all additional markers, for a FPR of 5%, the detection rate for T21 reached 94-97.5% [11][12][13]. When all of these markers were added to a traditional combined test, the detection rate substantially increased to up to 100%, for a FPR of 2.4% [14] or 3.4% [15].…”

False-Positive Rate in First-Trimester Screening Based on Ultrasound and Cell-Free DNA versus First-Trimester Combined Screening with Additional Ultrasound Markers

“…For the same cutoff, the detection rate for trisomy 18, 13, triploidy, and Turner syndrome was 96% [17]. Other study groups have found similar results [18][19][20].…”

Diagnostic value of ultrasonographic combining biochemical markers for Down syndrome screening in first trimester: a meta‐analysis

“…Eight performed the test of NT alone, including 103 568 patients. Most of the studies (8/24) chose the cut‐off value of 1 in 300 as the positive result, six studies chose the cut‐off value of 1 in 250, three studies were 1 in 270, one was 2.5 mm, one was 95 th centile, one was 99 th centile and one used 1.5 MoM (multiples of the calculated regressed median), respectively. Most of the studies (21/24) were published in English, and the remaining three articles were published in Chinese.…”