NIPT/NIPT plus combined with ultrasound in screening fetal chromosomal abnormalities：a retrospective study

Abstract Introduction: This is a retrospective study of 306 pregnant women of which 182 had genetic testing with NIPT plus and CMA, and another 124 had genetic testing with standard NIPT and CMA. To compare the clinical performance of NIPT and NIPT plus in prenatal evaluation, and the NIPT results were compared to CMA as the gold standard to analyze the diagnostic efficiency of the two NIPT methods. Methods: By analyzing the NIPT Plus/NIPT results and correlating them with the ultrasound results, we evaluated the accuracy and clinical utility of this approach. Finally, the results of CMA were compared as the gold standard to analyze the diagnostic efficiency of the two methods. Results: It showed that the combined diagnosis of NIPT Plus and ultrasound had a higher detection rate than the combined diagnosis of NIPT and ultrasound. The positive predictive value of the combined diagnosis of NIPT and ultrasound was as high as 100% in our study. Conclusion: NIPT plus has a higher false positive rate, which emphasizes the need for combining ultrasound in the screening process to provide clinical guidance. Screening for sex chromosome aneuploidy in fetuses, using NIPT alone, may be superior to combined screening with ultrasound.