P02.03: Concurrent first trimester screening and cell free DNA testing for aneuploidy detection

2015 ◽  
Vol 46 ◽  
pp. 126-126
Author(s):  
M. Naqvi ◽  
B. Wylie ◽  
J. Ecker ◽  
A. Kaimal
2016 ◽  
Vol 214 (1) ◽  
pp. S326 ◽  
Author(s):  
Arin Buresch ◽  
Mara Rosner ◽  
Barrie Suskin ◽  
Francine Einstein ◽  
Emnonila Bircaj ◽  
...  

Author(s):  
Robin Wijngaard ◽  
Elena Casals ◽  
Imma Mercadé ◽  
Javier Laguna ◽  
Irene Madrigal ◽  
...  

Introduction: The introduction of prenatal cell-free DNA as a screening test has surpassed traditional combined first-trimester screening (cFTS) in the detection of common trisomies. However, its current limitation in detecting only common trisomies is affecting the diagnostic yield for other clinically significant chromosomal abnormalities. Methods: In efforts to optimize the detection of fetuses with genetic abnormalities, we have analyzed the relationship between the cFTS risk score and biomarkers with atypical chromosomal abnormalities. Furthermore, we have evaluated the impact of prenatal cell-free DNA screening on the detection of chromosomal abnormalities in our population. For these purposes, we performed a retrospective study of 877 singleton pregnancies who underwent chromosomal microarray analysis (CMA) between 2013 to 2020 and for whom first-trimester screening data were available. Results: The results demonstrated that low levels of free beta human chorionic gonadotropin (β-hCG) (≤ 0.37 MoM) and increased fetal nuchal translucency (NT) (≥ 3.5mm) were statistically associated with the presence of atypical chromosomal abnormalities. In fact, the risk of pathogenic CMA results increased from 6% to 10% when fetal NT was increased and from 6% to 20% when a low serum β-hCG level was detected in the high-risk cFTS group. Moreover, our results showed that altered serum levels of β-hCG can have a substantial impact on the early detection of clinically relevant copy number variants. Discussion/Conclusion: Traditional cFTS can potentially identify a substantial proportion of atypical chromosomal aberrations, and women with increased NT or low maternal serum β-hCG levels are at increased risk of having pathogenic CMA results. Our results may help clinicians and women decide whether invasive testing or prenatal cell-free DNA screening testing are more appropriate for each situation.


Author(s):  
Ioan Suciu ◽  
Slavyana Galeva ◽  
Samira Abdel Azim ◽  
Lucian Pop ◽  
Oana Toader

2020 ◽  
Vol 40 (11) ◽  
pp. 1482-1488
Author(s):  
Sonia Migliorini ◽  
Gabriele Saccone ◽  
Fiora Silvestro ◽  
Giulia Massaro ◽  
Bruno Arduino ◽  
...  

Author(s):  
Gokhan Goynumer ◽  
Cihat Sen ◽  
Olus Api ◽  
Murat Yayla

ABSTRACT Prenatal screening for fetal aneuploidies has been focused on mainly Down syndrome in the last 40 years. The method of screening has changed from maternal age in the 1970s, with a detection rate of 30 and 5% false positive rate (FPR), to a combination of maternal age and second-trimester serum biochemical markers (triple test and quadruple test) in the 1980s and 1990s, with 60 to 75% detection rate and 5% false positive rate (FPR). Following this, the era of first trimester screening for Down syndrome has started with the clinical implementation of fetal nuchal translucency screening. The combination of maternal age, NT thickness and serum free beta-human chorionic gonadotropin (â-hCG) and pregnancy-associated plasma protein A (PAPP-A) in the first trimester has yielded a 90% detection rate with a 5% FPR. Starting from the year 2008, studies have shown that the performance of screening may be improved by analysis of cell-free deoxyribonucleic acid (DNA) (cfDNA) in maternal blood. Several studies in the last few years have reported the clinical validation of cell free fetal DNA test in the maternal serum in screening for trisomies 21, 18, and 13 and sex chromosome aneuploidies. Its widespread use is limited by the relatively high cost of the test and the lack of consensus about the optimal way for its clinical implementation. Until the optimal way of incorporating cfDNA into the clinical practice gets identified, it would be wise not to substitute cfDNA testing in place of first-trimester screening for fetal defects and other major complications of pregnancy. Furthermore, it would be preferable for clinicians managing individual patients not to counsel them for their result as positive or negative, rather the clinicians should use the risk estimate from the first-line method of screening as the prior risk and modify this by the appropriate positive or negative likelihood ratio from the cfDNA test. How to cite this article Sen C, Api O, Yayla M, Goynumer G. Cell-free DNA Testing: Where are We now? Donald School J Ultrasound Obstet Gynecol 2016;10(2):172-177.


2018 ◽  
Vol 40 (02) ◽  
pp. 176-193 ◽  
Author(s):  
Peter Kozlowski ◽  
Tilo Burkhardt ◽  
Ulrich Gembruch ◽  
Markus Gonser ◽  
Christiane Kähler ◽  
...  

AbstractFirst-trimester screening between 11 + 0 and 13 + 6 weeks with qualified prenatal counseling, detailed ultrasound, biochemical markers and maternal factors has become the basis for decisions about further examinations. It detects numerous structural and genetic anomalies. The inclusion of uterine artery Doppler and PlGF screens for preeclampsia and fetal growth restriction. Low-dose aspirin significantly reduces the prevalence of severe preterm eclampsia. Cut-off values define groups of high, intermediate and low probability. Prenatal counseling uses detection and false-positive rates to work out the individual need profile and the corresponding decision: no further diagnosis/screening – cell-free DNA screening – diagnostic procedure and genetic analysis. In pre-test counseling it must be recognized that the prevalence of trisomy 21, 18 or 13 is low in younger women, as in submicroscopic anomalies in every maternal age. Even with high specificities, the positive predictive values of screening tests for rare anomalies are low. In the general population trisomies and sex chromosome aneuploidies account for approximately 70 % of anomalies recognizable by conventional genetic analysis. Screen positive results of cfDNA tests have to be proven by diagnostic procedure and genetic diagnosis. In cases of inconclusive results a higher rate of genetic anomalies is detected. Procedure-related fetal loss rates after chorionic biopsy and amniocentesis performed by experts are lower than 1 to 2 in 1000. Counseling should include the possible detection of submicroscopic anomalies by comparative genomic hybridization (array-CGH). At present, existing studies about screening for microdeletions and duplications do not provide reliable data to calculate sensitivities, false-positive rates and positive predictive values.


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