Parental willing to take invasive diagnosis after Expanded Noninvasive Prenatal Testing (expanded NIPT) in a cohort of 24768 cases

Abstract BackgroundThe main aims of the study were to investigate the performance of expanded noninvasive prenatal test (expanded NIPT) in screening for common trisomies, sex chromosomal aneuploidies (SCAs), rare autosomal aneuploidies (RATs) and copy number variations (CNVs) and parental willing to taking invasive prenatal diagnosis after expanded NIPT in China.ResultsOf the 24,736 cases, successful follow-up was conducted in 92.2% (411/446) cases. The sensitivity of expanded NIPT test was 98.61%,90.91% and 100% and specificity was 99.91%,99.95% and 99.87% for the detection of trisomies 21, 18 and 13 respectively. Expanded NIPT detected 45, XO, 47, XXX, 47, XXY, XYY syndrome, RATs and CNVs with positive predictive values of 57.39%, 19.61%, 75%, 79.41%, 77.78%, 10% and 56.25% respectively. The women carrying fetuses with T21/T18/T13 underwent invasive prenatal diagnosis and terminated their pregnancies at higher rates than those positive for SCAs, RATs and CNVs.ConclusionsOur study demonstrates that the expanded NIPT detects fetal trisomies 21,18 and 13 with high sensitivity and specificity. The accuracy of detecting SCAs, RATs and CNVs is still relatively poor and needed to be improved. With a positive expanded NIPT result, the women at high risk for common trisomies are more willing to take invasive prenatal diagnosis and terminate their pregnancies.* the first two authors contribute equally to this study.