目的:定义正常基因检测和妊娠中期异常扫描后,颈项透明(NT)大于或等于3.5mm的胎儿发生发病相关结局的残余风险。
方法:总共114个胎儿的孤立NT为3.5毫米或更大,正常核型,和基于阵列的比较基因组杂交(array-CGH)被纳入并分为三组:NT3.5-4.5毫米,NT4.5-6毫米,和NT大于6毫米。对所有胎儿进行了RASopathy测试和超声随访。我们评估了:(1)遗传性疾病的发生率;(2)结构异常的发生率;(3)妊娠结局;(4)在正常的RASopathy测试和中期异常扫描之前(第1点)和之后(第2点)的长期儿科结局。
结果:在正常核型和阵列CGH后,对于NT3.5-4.5mm,发病率相关结局的残余风险为24.64%,NT4.5-6mm为25%,NT大于6mm为76.47%。在正常的RASopathy测试和中期异常扫描后,残余风险降低到7.14%,8.69%,三组中占33.3%,分别。
结论:在NT为3.5mm或更高且核型和阵列CGH均正常的胎儿中,发病率相关结局的发生率取决于NT大小.正常的RASopathy测试和中期超声检查令人放心,但与普通人群相比,发病率相关结局的残余风险增加。特别是如果NT大于6毫米。
OBJECTIVE: To define the residual risk of morbidity-related outcome in fetuses with nuchal translucency (NT) of 3.5 mm or more after normal genetic testing and mid-trimester anomaly scan.
METHODS: A total of 114 fetuses with isolated NT of 3.5 mm or more, normal karyotype, and array-based comparative genomic hybridization (array-CGH) were included and divided in three groups: NT 3.5-4.5 mm, NT 4.5-6 mm, and NT greater than 6 mm.
RASopathy testing and ultrasound follow up were performed in all fetuses. We evaluated: (1) incidence of genetic disorders; (2) incidence of structural abnormalities; (3) pregnancy outcome; (4) long-term pediatric outcome before (point 1) and after (point 2) a normal
RASopathy testing and mid-trimester anomaly scan.
RESULTS: After normal karyotype and array-CGH the residual risk of morbidity-related outcome was 24.64% for NT 3.5-4.5 mm, 25% for NT 4.5-6 mm and 76.47% for NT more than 6 mm. After a normal
RASopathy testing and mid-trimester anomaly scan the residual risks decreased to 7.14%, 8.69%, and 33.3% in the three groups, respectively.
CONCLUSIONS: In fetuses with an NT of 3.5 mm or more and both normal karyotype and array-CGH, the rate of morbidity-related outcome depends on NT size. A normal
RASopathy testing and mid-trimester ultrasound are reassuring but the residual risk of morbidity-related outcome is increased compared with the general population, particularly if NT is greater than 6 mm.