Premium
Incidence of chromosomal abnormalities in fetuses with first trimester ultrasound anomalies and a low‐risk cell‐free DNA test for common trisomies
Author(s) -
Persico Nicola,
Boito Simona,
Volpe Paolo,
Ischia Benedetta,
Gentile Mattia,
Ronzoni Luisa,
De Robertis Valentina,
Fabietti Isabella,
Olivieri Claudiana,
Periti Enrico,
Ficarella Romina,
Silipigni Rosamaria,
Rembouskos Georgios
Publication year - 2020
Publication title -
prenatal diagnosis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.956
H-Index - 97
eISSN - 1097-0223
pISSN - 0197-3851
DOI - 10.1002/pd.5799
Subject(s) - trisomy , cell free fetal dna , obstetrics , medicine , fetus , incidence (geometry) , aneuploidy , pregnancy , prenatal diagnosis , gynecology , chromosome , biology , genetics , physics , gene , optics
Objective To examine the incidence and type of chromosomal abnormalities in fetuses with first trimester ultrasound anomalies and a low‐risk cfDNA test for common trisomies. Methods In 486 singleton pregnancies undergoing invasive testing after combined screening, a detailed first trimester ultrasound assessment was carried out and a maternal blood sample was sent for cfDNA analysis. Ultrasound and cfDNA data were analyzed in relation to fetal karyotype. Results Invasive testing demonstrated a chromosomal abnormality in 157 (32.3%) of 486 fetuses. In 348 cases with a low‐risk cfDNA test for common trisomies, NT ≥ 3.5 mm and/or a major structural defect were observed in 92 (26.4%) fetuses. A chromosomal abnormality was found in 17 (18.5%; 95%CI 10.55‐26.41) of these pregnancies, including 1 (1.1%) case of trisomy 21 and 16 (17.4%) fetuses with abnormalities different from common trisomies. The respective incidence in the 256 cases with a low‐risk cfDNA test result and no ultrasound anomalies was 2.3% (95% CI 0.49‐4.20; n = 6). Conclusions In fetuses with first trimester ultrasound anomalies and a low‐risk cfDNA result for trisomy 21, 18 and 13, diagnostic testing should be offered with the main objective to detect chromosomal abnormalities beyond common trisomies.