Patient characteristics and clinical indication.

BackgroundCell-free DNA (cf-DNA) screening for common trisomies has been increasingly assimilated into prenatal care. In this study, we evaluated the Z-score accuracy and the effectiveness of non-invasive prenatal testing (NIPT) for trisomies 21, 18, and 13 using cf-DNA, and further analyze pregnancy outcomes of NIPT-positive pregnant women.MethodsThis retrospective study analyzed pregnancies that yielded positive NIPT results at Shaoxing Maternity and Child Health Care Hospital between 01/01/2017 and 31/12/2022. Invasive prenatal diagnosis (IPD) confirmed the positive NIPT findings. Logistic regression analysis was applied to correlation analysis of Z-scores and positive predictive value (PPV). Accuracy of Z-score was evaluated through receiver operating characteristic (ROC) curve analysis. Data regarding basic characteristics, prenatal diagnosis results, and pregnancy outcomes were collected.ResultsIn total,257 high-risk cases of trisomy 21, 18, and 13 were identified. Among these,193 pregnancies underwent invasive prenatal diagnosis (IPD) in our institution, the PPV was 75.44% for T21,45.28% for T18, and 17.86% for T13. A significant association between Z-scores and PPVs were revealed by logistic regression(p ConclusionsThe study demonstrates that the Z-score is valuable in accurately assessing NIPT results. Consequently, clinicians can provide more efficient prenatal genetic counseling by utilizing a specific reference value for the Z-score.【背景】针对常见三体综合征的无细胞DNA（cell-free DNA, cf-DNA）筛查已愈发广泛地应用于临床产前保健领域。本研究旨在评估基于无细胞DNA的无创产前检测（non-invasive prenatal testing, NIPT）对21-三体、18-三体及13-三体的Z值（Z-score）准确性与检测效能，并进一步分析NIPT阳性孕妇的妊娠结局。 【方法】本研究为回顾性研究，纳入2017年1月1日至2022年12月31日期间于绍兴市妇幼保健院检出NIPT阳性的妊娠病例。所有NIPT阳性结果均经侵入性产前诊断（invasive prenatal diagnosis, IPD）确认。采用Logistic回归分析对Z值与阳性预测值（positive predictive value, PPV）进行相关性分析；通过受试者工作特征（receiver operating characteristic, ROC）曲线分析评估Z值的诊断效能。收集研究对象的基础临床特征、产前诊断结果及妊娠结局相关数据。 【结果】本研究共检出257例21-三体、18-三体及13-三体高风险病例。其中193例在本院接受了侵入性产前诊断，21-三体的阳性预测值为75.44%，18-三体为45.28%，13-三体为17.86%。Logistic回归分析显示，Z值与阳性预测值之间存在显著相关性（p 【结论】本研究证实，Z值可精准评估无创产前检测结果，临床医师可通过参考特定Z值参考界值，为孕妇提供更为高效的产前遗传咨询服务。