Prenatal diagnosis of chromosomal aberrations by chromosomal microarray analysis in foetuses with ventriculomegaly

Ventriculomegaly is considered to be linked to abnormal neurodevelopment outcome. The aim of this retrospective study was to investigate the current applications of chromosomal microarray analysis (CMA) in foetuses with ventriculomegaly. A total of 548 foetuses with ventriculomegaly detected by prenatal ultrasound underwent single nucleotide polymorphism (SNP) array testing and were subjected to long-term follow-up. The overall prevalence of chromosomal aberrations was 7.30% (40/548), including 4.20% (23/548) with pathogenic/likely pathogenic copy number variants. The incidence of chromosomal aberrations was significantly higher in foetuses with bilateral ventriculomegaly than in those with unilateral ventriculomegaly (10.56% vs. 5.71%, P=0.040), in foetuses with non-isolated ventriculomegaly than in those with isolated ventriculomegaly (12.99% vs. 2.38%, P<0.0001), and in foetuses with severe ventriculomegaly than in those with mild-to-moderate ventriculomegaly (23.08% vs. 6.51%, P=0.005). The outcome in foetuses with mild ventriculomegaly was significantly better than in those with moderate ventriculomegaly (95.60% vs. 84.00%, P=0.003). Thus, CMA should be regarded as the first-tier test for prenatal diagnosis of foetal ventriculomegaly, especially in foetuses with bilateral or non-isolated ventriculomegaly. The outcome of foetuses with mild ventriculomegaly is favourable; however, there is an increased risk of neurodevelopmental disabilities in foetuses with moderate ventriculomegaly.