Abstract：
OBJECTIVE: To prospectively evaluate the prognosis of fetuses diagnosed with micrognathia using prenatal ultrasound screening.
METHODS: Between January 2019 and December 2022, a normal range of IFA to evaluate the facial profile in fetuses with micrognathia in a Chinese population between 11 and 20 gestational weeks was established, and the pregnancy outcomes of fetal micrognathia were described. The medical records of these pregnancies were collected, including family history, maternal demographics, sonographic findings, genetic testing results, and pregnancy outcomes.
RESULTS: Ultrasound identified 25 patients with fetal micrognathia, with a mean IFA value of 43.6°. All cases of isolated fetal micrognathia in the initial scans were non-isolated in the following scans. A total of 78.9% (15/19) cases had a genetic cause confirmed, including 12 with chromosomal abnormalities and 3 with monogenic disorders. Monogenic disorders were all known causes of micrognathia, including two cases of campomelic dysplasia affected by SOX9 mutations and one case of mandibulofacial dysostosis with an EFTUD2 mutation. In the end, 19 cases were terminated, 1 live birth was diagnosed as Pierre Robin syndrome, and 5 cases were lost to follow-up.
CONCLUSIONS: IFA is a useful indicator and three-dimensional ultrasound is a significant support technique for fetal micrognathia prenatal diagnosis. Repeat ultrasound monitoring and genetic testing are crucial, with CMA recommended and Whole exome sequencing performed when normal arrays are reported. Isolated fetal micrognathia may be an early manifestation of monogenic disorders.
METHODS: Between January 2019 and December 2022, a normal range of IFA to evaluate the facial profile in fetuses with micrognathia in a Chinese population between 11 and 20 gestational weeks was established, and the pregnancy outcomes of fetal micrognathia were described. The medical records of these pregnancies were collected, including family history, maternal demographics, sonographic findings, genetic testing results, and pregnancy outcomes.
RESULTS: Ultrasound identified 25 patients with fetal micrognathia, with a mean IFA value of 43.6°. All cases of isolated fetal micrognathia in the initial scans were non-isolated in the following scans. A total of 78.9% (15/19) cases had a genetic cause confirmed, including 12 with chromosomal abnormalities and 3 with monogenic disorders. Monogenic disorders were all known causes of micrognathia, including two cases of campomelic dysplasia affected by SOX9 mutations and one case of mandibulofacial dysostosis with an EFTUD2 mutation. In the end, 19 cases were terminated, 1 live birth was diagnosed as Pierre Robin syndrome, and 5 cases were lost to follow-up.
CONCLUSIONS: IFA is a useful indicator and three-dimensional ultrasound is a significant support technique for fetal micrognathia prenatal diagnosis. Repeat ultrasound monitoring and genetic testing are crucial, with CMA recommended and Whole exome sequencing performed when normal arrays are reported. Isolated fetal micrognathia may be an early manifestation of monogenic disorders.
摘要：
目的：前瞻性评估产前超声筛查诊断为小颌畸形的胎儿的预后。
方法：在2019年1月至2022年12月之间，建立了IFA的正常范围，以评估11至20孕周的中国人群中小颌畸形胎儿的面部轮廓，并描述了胎儿小颌畸形的妊娠结局。收集了这些怀孕的医疗记录，包括家族史,孕产妇人口统计学，超声检查结果，基因检测结果,和妊娠结局。
结果：超声诊断出25例胎儿小颌畸形，平均IFA值为43.6°。初始扫描中的所有孤立的胎儿小颌畸形病例在以下扫描中是非孤立的。共有78.9%(15/19)的病例有遗传原因确诊,包括12例染色体异常和3例单基因疾病。单基因疾病都是小颌畸形的已知原因，包括2例受SOX9突变影响的钟形发育不良和1例EFTUD2突变的下颌面骨发育不良。最后,19例被终止，1个活产被诊断为皮埃尔·罗宾综合征，5例失访。
结论：IFA是一个有用的指标，三维超声是胎儿小颌畸形产前诊断的重要支持技术。重复超声监测和基因检测至关重要，推荐CMA，报告正常阵列时进行全外显子组测序。孤立的胎儿小颌畸形可能是单基因疾病的早期表现。
方法：在2019年1月至2022年12月之间，建立了IFA的正常范围，以评估11至20孕周的中国人群中小颌畸形胎儿的面部轮廓，并描述了胎儿小颌畸形的妊娠结局。收集了这些怀孕的医疗记录，包括家族史,孕产妇人口统计学，超声检查结果，基因检测结果,和妊娠结局。
结果：超声诊断出25例胎儿小颌畸形，平均IFA值为43.6°。初始扫描中的所有孤立的胎儿小颌畸形病例在以下扫描中是非孤立的。共有78.9%(15/19)的病例有遗传原因确诊,包括12例染色体异常和3例单基因疾病。单基因疾病都是小颌畸形的已知原因，包括2例受SOX9突变影响的钟形发育不良和1例EFTUD2突变的下颌面骨发育不良。最后,19例被终止，1个活产被诊断为皮埃尔·罗宾综合征，5例失访。
结论：IFA是一个有用的指标，三维超声是胎儿小颌畸形产前诊断的重要支持技术。重复超声监测和基因检测至关重要，推荐CMA，报告正常阵列时进行全外显子组测序。孤立的胎儿小颌畸形可能是单基因疾病的早期表现。
