颈部透明层增厚与染色体异常的相关分析

目的:评估颈部透明层(NT)增厚胎儿的染色体异常风险,探讨染色体微阵列分析(CMA)在NT增厚时的应用情况。方法:回顾性分析374例于广州医科大学附属第三医院诊断为NT增厚胎儿的超声及CMA结果。结果:374例NT增厚病例中,109例(29.1%)染色体异常。在NT值为2.5~3.4mm、3.4~4.4mm、4.5~5.4mm、≥5.5mm4组中每组病例数及染色体异常例数分别为114例,26例(22.8%);150例,33例(22.0%);55例,19例(34.5%);55例,31例(56.4%)。各NT值组染色体异常比较差异有统计学意义,NT增厚的程度与胎儿发生染色体异常正相关(ρ=0.208,P<0.001)。NT增厚且合并其他超声异常者共64例,染色体异常率为60.9%(39/64),与单纯NT增厚胎儿染色体异常率(22.6%)比较,差异有统计学意义(χ^2=37.794,P<0.001)。结论:早孕期胎儿NT增厚与染色体异常、其他超声异常密切相关;NT增厚的程度越大,胎儿发生染色体异常的风险越高。与单纯NT增厚胎儿相比,合并其他超声异常的胎儿染色体异常检出率更高。

Correlation between Increased Nuchal Translucency and Chromosomal Abnormalities

Objective:To estimate the risk of chromosomal abnormalities and explore the application of chromosomal microarray analysis(CMA)in fetuses with increased nuchal translucency(NT).Methods:A total of 374 fetuses diagnosed as increased NT from the third affiliated hospital of Guangzhou Medical Univ-ersity were retrospectively studied to analyze the ultrasound and CMA results.Results:Of 374 fetuses with increased NT,109(29.1%)cases had abnormal CMA findings.All cases were divided into four groups according to the NT measurement.In group NT between 2.5-3.4 mm,3.5-4.4 mm,4.5-5.4 mm and NT≥5.5 mm,the number of cases and the number of chromosomal abnormalities cases were 114,26(22.8%);150,33(22.0%);55,19(34.5%);55,31(56.4%),respectively.There was significant difference in chromosomal abnormalities among NT groups,and the degree of fetal NT thickness was positively correlated with chromosomal abnormalities(ρ=0.208,P<0.05).There were 64 cases with increased NT and other ultrasound abnormalities,and 39 cases of these presented chromosomal abnormalities(60.9%).Compared the fetal chromosomal abnormalities between the cases with other ultrasound abnormalities and the cases of isolate increased nuchal translucency,the difference was significant(χ^2=37.794,P<0.001).Conclusions:Fetuses with increased NT have a greater incidence of chromosomal abnormalities,structural malformations and adverse pregnancy outcomes.The prevalence of chromosomal defects and adverse pregnancy outcomes increases exponentially with NT thickness.The abnormal chromosomal detection rate of fetuses with increased NT and other ultrasound abnormalities was higher than that with isolate increased nuchal translucency.