First-trimester contingent screening for trisomies 21, 18 and 13 by biomarkers and maternal blood cell-free DNA testing.

Abstract

OBJECTIVE:

To examine potential performance of screening for trisomies by cell-free (cf) DNA testing in maternal blood contingent on results of first-line testing by combinations of fetal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index (DV PIV), and serum-free β-human chorionic gonadotropin (β-hCG), pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PLGF) and α-fetoprotein (AFP).

METHODS:

Performance was estimated for firstly, screening by cfDNA in all pregnancies and secondly, cfDNA testing contingent on results of first-line testing by combinations of ultrasound and biochemical markers.

RESULTS:

In first-line screening by cfDNA testing, the detection rate for trisomy 21 and trisomies 18 or 13 would be 99 and 96%, respectively, after invasive testing in 1% of the population. In contingent screening, a detection rate of 98% for trisomy 21 and 96% for trisomy 18 or 13, at an invasive testing rate of 0.7%, can be achieved by carrying out cfDNA testing in about 35, 20 and 11% of cases identified by first-line screening with the combined test alone (age, NT, FHR, β-hCG, PAPP-A), the combined test plus PLGF and AFP and the combined test plus PLGF, AFP and DV PIV, respectively.

CONCLUSIONS:

Effective first-trimester screening for trisomies can be achieved by contingent screening incorporating biomarkers and cfDNA testing.

• Authors: K H Nicolaides, A Syngelaki, L C Poon, M M Gil, D Wright
• Journal: Fetal diagnosis and therapy (Fetal Diagn Ther) Vol. 35 Issue 3 Pg. 185-92 ( 2014) ISSN: 1421-9964 [Electronic] Switzerland
• PMID: 24192489 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2013 S. Karger AG, Basel.

Chemical References

• Biomarkers
• DNA

Topics

• Biomarkers (blood)
• Cell-Free System (physiology)
• Chromosome Disorders (blood, diagnosis, genetics)
• Chromosomes, Human, Pair 13 (genetics)
• Chromosomes, Human, Pair 18 (genetics, metabolism)
• DNA (genetics)
• Down Syndrome (blood, diagnosis, genetics)
• Female
• Humans
• Maternal Serum Screening Tests (methods, standards)
• Pregnancy
• Pregnancy Trimester, First (blood, genetics)
• Trisomy (diagnosis, genetics)
• Trisomy 13 Syndrome
• Trisomy 18 Syndrome