Coello-Cahuao E, Sánchez-Durán MÁ, Calero I, Higueras MT, García MA, Rodó C, Maiz N, Plaja Rustein A, Castells-Sarret N, Mediano-Vizuete C, Carreras E. Array study in fetuses with nuchal translucency above the 95th percentile: a 4-year observational single-centre study. Arch Gynecol Obstet. 2022 Apr 29. doi: 10.1007/s00404-022-06564-7. Epub ahead of print. PMID: 35486155.
Purpose: To evaluate the performance of chromosomal microarray analysis (CMA) in fetuses with nuchal translucency (NT) > 95th percentile. Secondary objectives were to analyze these results according to NT thickness, below or above 3.5 mm, and those without associated anomalies.
Methods: This observational single-cohort study was conducted between 2015 and 2018 in fetuses with NT > 95th percentile. Following an invasive test, quantitative fluorescence-polymerase chain reaction (QF-PCR) was performed, and if normal, CMA was performed. Pathogenic copy number variants (CNVs), non-reported pathogenic CNV, pathogenic autosomal recessive variants and variants of unknown significance (VUS) were analysed.
Results: One-hundred and sixty-two fetuses with NT > 95th percentile, normal QF-PCR and CMA were included. Amongst 128 fetuses with NT between the 95th percentile and 3.5 mm, one (0.8%) had a pathogenic CNV, four (3.1%) had non-reported pathogenic CNV, one (0.8%) had pathogenic autosomal recessive variant and 13 (10.2%) had VUS. Amongst 34 fetuses with NT ≥ 3.5 mm, four (11.8%) had pathogenic CNV, one (2.9%) had non-reported pathogenic CNV, one (2.9%) had pathogenic autosomal recessive variant and four (11.8%) had VUS. Four in 162 (2.5%) fetuses had CNVs at the chromosome 16p13.11 region. Amongst 154 fetuses without structural abnormalities and normal QF-PCR, three (1.9%) had a pathogenic CNV, 5 (3.2%) had non-reported pathogenic CNV, one (0.6%) autosomal recessive pathogenic CNV and 16 (10.4%) had VUS.
Conclusion: Pathogenic CNVs were found in 1% of fetuses with an NT thickness between the 95th percentile and 3.5 mm and in 12% of fetuses with NT ≥ 3.5 mm. CNVs were found at the 16p13.11 region in 2.5% of cases.