Is high fetal nuchal translucency associated with submicroscopic chromosomal abnormalities on array CGH?

Abstract

ABSTRACT

Enlarged NT (≥3.5 mm) in the first trimester – not all chromosome aberrations can be detected by NIPT

“…Our results show that the prevalence of submicroscopic aberrations in fetuses with enlarged NT resembles the prevalence in fetuses without ultrasound anomalies. This confirms previous results published by Huang and colleagues [39]. Therefore, in our opinion larger unselected cohorts with enlarged NT should be published to assess the actual risk of a pathogenic submicroscopic unbalanced chromosome aberration when an enlarged NT is diagnosed in the first trimester.…”

“…These differences in frequencies of chromosomal aberrations in published cohorts were observed before [42] and it may be a consequence of both cohort selection and differences in array design. Many of previously reported cohorts were either retrospectively tested and highly selected [38, 39] or included a heterogeneous group of fetuses with and without additional ultrasound anomalies detected in both first and second trimester [36, 38, 44, 45]. Our results show that the prevalence of submicroscopic aberrations in fetuses with enlarged NT resembles the prevalence in fetuses without ultrasound anomalies.…”

Routine use of array comparative genomic hybridization (aCGH) as standard approach for prenatal diagnosis of chromosomal abnormalities. Clinical experience of 1763 prenatal cases

“…Huang et al . recently published a study in which they examined the association of increased NT (≥3.5 mm) and CMA findings in 215 pregnancies with normal karyotype . They found no pathogenic CNVs that could be associated with high NT and only three CNVs that were classified as VOUS, concluding that submicroscopic chromosomal abnormalities detected only by array CGH may not be associated with isolated increased fetal NT.…”

Women's preference for non‐invasive prenatal DNA testing versus chromosomal microarray after screening for Down syndrome: a prospective study

“…Women carrying fetuses with structural abnormalities or hydrops were counselled to undergo an invasive test because of the increased risk of chromosomal abnormalities or other copy number variants (CNVs). Women with NT ≥ 3.5 mm were counselled that the risk of pathogenic CNVs was 1.4%, based on previous studies …”