METHODS: A total of 2 745 women with twin-pregnancies were subjected for NIPT screening. Chromosomal karyotyping and chromosomal microarray analysis (CMA) were carried out on amniotic fluid samples from those with a high risk for fetal chromosome aneuploidies, and the diagnosis and pregnancy outcome were followed up. The sensitivity, specificity, positive predictive value and false positive rate of the NIPT were calculated.
RESULTS: Compared with other chromosomal abnormalities, NIPT had a higher efficacy for trisomy 21 and sex chromosomal aneuploidy (SCA) in twin pregnancies (with sensitivity being 100%, 100%, and specificity being 99.93%, 99.9%, respectively). It is difficult to evaluate the efficacy for trisomies 18 and 13 due to the limited data. For chromosome microdeletions and microduplications spanning 15 ~ 21 Mb, NIPT also had a certain detection rate. Compared with women with natural conception, NIPT had a higher detection rate for those with twin pregnancies by assisted reproduction (P < 0.05).
CONCLUSIONS: It is feasible to use NIPT for the detection of chromosome aneuploidies in women with twin pregnancies.
方法:共有2745名双胎妊娠妇女接受NIPT筛查。染色体核型分析和染色体微阵列分析(CMA)是对胎儿染色体非整倍体高风险的羊水样本进行的。随访诊断及妊娠结局。敏感性,特异性,计算NIPT的阳性预测值和假阳性率。
结果:与其他染色体异常相比,NIPT对双胎妊娠中的21三体和性染色体非整倍体(SCA)具有更高的疗效(敏感性为100%,100%,特异性为99.93%,99.9%,分别)。由于数据有限,很难评估三体18和13的疗效。对于染色体微缺失和跨越15~21Mb的微重复,NIPT也有一定的检出率。与自然受孕的女性相比,辅助生殖双胎妊娠的NIPT检出率较高(P<0.05)。
结论:使用NIPT检测双胎妊娠妇女的染色体非整倍体是可行的。