[Value of chromosomal microarray analysis for the prenatal diagnosis of pregnancy with high risk signaled by...

To explore the value of chromosomal microarray analysis (CMA) for the diagnosis of fetuses with high risk signaled by non-invasive prenatal testing (NIPT).

From June 2017 to August 2019, 628 pregnant women with high risk signaled by NIPT underwent invasive prenatal diagnosis. Amniotic fluid or cord blood samples were subjected to chromosomal karyotyping analysis or CMA. Pregnancy outcome and postnatal conditions of the fetuses were followed up.

The positive predictive value for trisomy 21, trisomy 18, trisomy 13, sex chromosome aneuploidy, other rare trisomies and copy number variants (CNVs) among the 628 women were 86.4% (127/147), 41.7% (30/72), 12.9% (4/31), 43.7% (101/231), 16.5% (14/85) and 52.2% (35/67), respectively. In 218 samples with normal karyotype, 5.5% (12/218) of additional pathogenic CNVs and 2.3% (5/218) of loss of heterozygosity were detected by CMA.

CMA combined with karyotyping analysis can be used as first-tier test for prenatal diagnosis for women with high-risk signaled by NIPT.