目的:这项研究的目的是评估非侵入性产前检测(NIPT)在双胎妊娠中检测染色体非整倍体和拷贝数变异(CNVs)的性能。
方法:招募了2010年双胎妊娠妇女的队列。1331名患者选择了NIPT,679例患者选择扩大NIPT(NIPT-plus)。建议所有高危患者进行侵入性产前诊断。对所有参与者进行随访,直至出生后6个月。
结果:预测22例NIPT染色体异常的风险很高,其中14名孕妇接受了侵入性产前诊断。其中21三体3例,18三体1例,7三体1例,性染色体非整倍体2例,和7例CNVs,其中确诊病例分别为2、1、0、1和0。通过NIPT-plus预测有20例染色体异常的高风险,其中16名孕妇接受了侵入性产前诊断。16例包括21三体1例,7三体1例,SCA7例,和7例CNVs,其中分别在1、0、3和2中得到确认。随访期间未发现假阴性结果。
结论:NIPT/NIPT-plus在双胎妊娠染色体非整倍体检测中具有优异的性能。但对于CNVs来说,NIPT的有效性很差,NIPT-plus具有一定的检测效率。值得注意的是,遗传前和遗传后咨询尤其重要,和绒毛膜,观念模式,临床适应症,胎儿分数应视为影响因素。
OBJECTIVE: The purpose of this study was to evaluate the performance of noninvasive prenatal testing (NIPT) for the detection of chromosomal aneuploidies and copy number variations (CNVs) in twin pregnancies.
METHODS: A cohort of 2010 women with twin pregnancies was recruited. 1331 patients opted for NIPT, and 679 patients opted for expanded NIPT (NIPT-plus). All high-risk patients were advised to undergo invasive prenatal diagnosis. All participants were followed up until 6 months after birth.
RESULTS: Twenty-two cases were predicted to have a high risk of chromosome abnormalities by NIPT, of which 14 pregnant women underwent invasive prenatal diagnosis. The 14 cases included 3 cases of trisomy 21, 1 case of trisomy 18, 1 case of trisomy 7, 2 cases of sex chromosome aneuploidies (SCAs), and 7 cases of CNVs, of which the confirmed cases numbered 2, 1, 0, 1, and 0, respectively. Twenty cases were predicted to have a high risk of chromosome abnormalities by NIPT-plus, of which 16 pregnant women underwent invasive prenatal diagnosis. The 16 cases included 1 case of trisomy 21, 1 case of trisomy 7, 7 cases of SCAs, and 7 cases of CNVs, of which were confirmed in 1, 0, 3, and 2, respectively. No false-negative result was reported during the follow-up period.
CONCLUSIONS: The NIPT/NIPT-plus has excellent performance in the detection of chromosome aneuploidies in twin pregnancies. But for CNVs, the effectiveness of NIPT is poor, and the NIPT-plus have a certain detection efficiency. It is worth noting that pre- and post-genetic counseling is especially important, and the chorionicity, mode of conception, clinical indications, and fetal fraction should be considered as influencing factors.