OC01.03: Atypical karyotypic abnormalities not identified through NIPT: the value of identifying fetal anomalies at the first or second trimester scan?

26 Citationer (Scopus)

Abstract

Objectives: Using a population based database including >200,000 Danish pregnancies, we have previously shown that 23% of all phenotypically important chromosomal abnormalities would not be diagnosed using currently available NIPT techniques. The aim of the current study was to assess how many of those would likely have been diagnosed because of ultrasound findings at the first- or second trimester scan Methods: A retrospective population-based analysis of all singleton pregnancies booked for combined first trimester screening (cFTS) in Denmark 2007-2011. Data concerning cFTS, anomalies diagnosed in the first and second trimester, and prenatal and postnatal karyotypes were collected from the Danish Fetal Medicine database. Karyotypes were classified according to whether the chromosome anomaly would have been detected by NIPT, and whether they were likely to affect phenotype Results: cFTS was completed in 193,638 pregnancies. 10,205 (5.3%) had a karyotype 1,122 (11.0%) were abnormal and 262 (23%) would have been missed by standard NIPT. At the first trimester scan, in thirty-five (13,4%) of these pregnancies a structural anomaly (n=14) or NT above 3.5 mm (n=21) as isolated finding was found. Forty-eight (18.3%) had spontaneous abortion (n=6) between the cFTS and the 2nd trim scan, or a structural anomaly (n=42) at the 2nd trim anomaly scan (<22w). 157 (59.9%) had no anomalies at the NT scan or 2nd trim anomaly scan, but 59 (37.6%) of those had a cFTS risk for T21 greater than 1 in 300, and 41 of those had TOP because of the diagnosed chromosomal anomaly. 142 (54.2%) had either abnormal cFTS or structural anomalies at the NT scan or 2nd trimester anomaly scan Conclusion: These data from a large, national cohort, show that 60% of cases with an atypical chromosomal abnormality, not detectable by NIPT, would not be diagnosed by first or second trimester ultrasound alone. Interestingly, 38% of these had an increased risk at cFTS and would therefore have been detected in our current screening program
OriginalsprogEngelsk
TidsskriftUltrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology
Vol/bind46
Udgave nummerS1
Sider (fra-til)1-2
Antal sider1
ISSN0960-7692
DOI
StatusUdgivet - 1 okt. 2015
Udgivet eksterntJa
BegivenhedISUOG World Congress - Los Angeles, USA
Varighed: 18 sep. 201122 sep. 2011

Konference

KonferenceISUOG World Congress
Land/OmrådeUSA
ByLos Angeles
Periode18/09/201122/09/2011

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