■关于增加的颈部半透明性(NT),使用的临界值在临床实践中是异质的,这项研究旨在评估产前检测对NT厚度不同的胎儿染色体异常和妊娠结局的疗效。为此类病例提供知情产前诊断和遗传咨询的数据。
■我们纳入了2,272名35岁以下的单胎妊娠孕妇,她们在2014年至2022年之间接受了侵入性产前诊断。该队列包括2,010个NT增加(≥2.5mm)的胎儿和262个NT正常但表现出单个软标记的胎儿。染色体微阵列(CMA)和拷贝数变异测序(CNV-seq)分析支持产前诊断。
■在NT≥2.5和≥3.0组中,数字染色体异常的检出率分别为15.4%(309/2,010)和17.3%(297/1,717),分别。致病性/可能致病性CNV发生率随NT厚度增加而增加(χ2=8.60,p<0.05),在NT4.5-5.4毫米组中,峰值为8.7%(22/254)。在NT值在2.5mm至2.9mm之间的胎儿中发现了18.4%的结构缺陷。孤立的NT增加组2.5-2.9mm和3.0-3.4mm的染色体异常率分别为6.7%(16/239)和10.0%(47/470),分别,差异无统计学意义(χ2=2.14,p>0.05)。NT厚度在2.5至2.9mm之间的胎儿与存在软标记或非致命性结构异常的胎儿相比,表现出显著更高的染色体异常风险(19.0%),与分离的NT增加范围在3.5至4.4mm(13.0%)的胎儿相比。妊娠终止率随NT厚度的增加而增加(χ2=435.18,p<0.0001),NT2.5-2.9mm组中的12.0%(30/249)到NT≥6.5mm组中的87.0%(141/162)。
■CMA或CNV-seq在识别NT厚度增加的怀孕中的基因组畸变方面表现出良好的性能。NT范围从2.5毫米到2.9毫米会增加胎儿染色体异常的风险,特别是当与其他软标记结合时。
UNASSIGNED: Regarding increased nuchal translucency (NT), the cutoff values used are heterogeneous in clinical practice, this study aims to assess the efficacy of prenatal detection for chromosomal abnormalities and pregnancy outcomes in fetuses with varying NT thicknesses, in order to provide data that supports informed prenatal diagnosis and genetic counseling for such cases.
UNASSIGNED: We included 2,272 pregnant women under 35 with singleton pregnancies who underwent invasive prenatal diagnosis between 2014 and 2022. The cohort comprised 2,010 fetuses with increased NT (≥2.5 mm) and 262 fetuses with normal NT but exhibiting a single soft marker. Prenatal diagnoses were supported by chromosomal microarray (CMA) and copy number variation sequencing (CNV-seq) analyses.
UNASSIGNED: The detection rates of numerical chromosomal abnormalities were 15.4% (309/2,010) and 17.3% (297/1,717) in the NT ≥2.5 and ≥ 3.0 groups, respectively. Pathogenic/likely pathogenic CNV incidence increased with NT thickness (χ2 = 8.60, p < 0.05), peaking at 8.7% (22/254) in the NT 4.5-5.4 mm group. Structural defects were found in 18.4% of fetuses with NT values between 2.5 mm and 2.9 mm. Chromosomal abnormality rates in the isolated increased NT groups of 2.5-2.9 mm and 3.0-3.4 mm were 6.7% (16/239) and 10.0% (47/470), respectively, with no statistical significance (χ2 = 2.14, p > 0.05). Fetuses with NT thickness between 2.5 and 2.9 mm combined with the presence of soft markers or non-lethal structural abnormalities exhibited a significantly higher chromosomal abnormality risk (19.0%) compared to fetuses with isolated increased NT ranging from 3.5 to 4.4 mm (13.0%). Pregnancy termination rates increased with NT thickness (χ2 = 435.18, p < 0.0001), ranging from 12.0% (30/249) in the NT 2.5-2.9 mm group to 87.0% (141/162) in the NT ≥ 6.5 mm group.
UNASSIGNED: CMA or CNV-seq exhibited good performance in identifying genomic aberrations in pregnancies with increased NT thickness. NT ranging from 2.5 mm to 2.9 mm elevated the risk of fetal chromosomal abnormalities, particularly when combined with other soft markers.