7529例高危孕妇的细胞遗传学分析

Cytogenetic analysis on 7 529 high-risk pregnant women

目的分析产前诊断技术在高危孕妇中的应用,指导孕期遗传咨询。方法回顾性分析7 529例因各种高危因素在河北省人民医院行产前诊断的临床病例资料。结果共检出染色体异常339例,异常检出率4.50%。不良孕产史者染色体异常检出率最高,达12.58%,超声占第二位。339例染色体异常核型中21-三体综合征占总异常核型的25.07%(85/339),55.16%(187/339)有超声软指标存在;因血清学筛查高危产前诊断确诊染色体异常核型中,除约1/2与21、18号染色体有关外,还涉及另外15种异常核型。因单一异常因素检出胎儿染色体异常79例,异常检出率为1.05%(79/7 529)。结论先天愚型是出生缺陷中发病率最高的疾病,在产前近半数的染色体病与21、18、13号和X、Y这5条染色体的数目和结构异常有关,有过不良孕产史的孕妇染色体异常检出率最高。唐氏血清学筛查和超声软指标在发现异常胎儿中发挥重要作用,单一异常因素对出生缺陷的检出作用不容忽视,在进行遗传咨询时应谨慎向孕妇及其家属交代这些风险的存在。

Objective To analyze the application of prenatal diagnosis technology in high-risk pregnant women in order to guide prenatal genetic counseling. Methods The clinical data of 7 529 cases receiving prenatal diagnosis because of various risk factors in the hospital were analyzed retrospectively. Results A total of 339 cases were diagnosed as chromosomal abnormalities, the detection rate was 4. 50%. The detection rate of chromosomal abnormalities among the eases with adverse pregnancy history was the highest, which was 12. 58%, followed by ultrasound screening. Among 339 cases with abnormal karyotypes, the cases with trisomy 21 accounted for 25. 07% （85/339） , 55. 16% （187/339） of the cases had ultrasonic soft markers; among the cases with abnormal karyotypes diagnosed definitely in prenatal examination by serological screening, other 15 kinds of abnormal karyotypes were involved besides half of the cases associated with chromosome 21 and chromosome 18. Seventy-nine cases were found with fetal chromosomal abnormalities induced by a single abnormal factor, the detection rate was 1.05% （79/7 529） . Conclusion Down＇s syndrome is the most common birth defect among all the congenital diseases. Nearly half of the chromosomal diseases are associated with the abnormalities of numbers and structure of chromosome 21, 18, 13, X, Y. The detection rate of chromosomal abnormalities is the highest in pregnant women with adverse pregnancy history. Serological screening for Down＇s syndrome and ultrasonic soft markers play important roles in detection of fetal abnormalities. The importance of only single abnormal factor for birth defects should not be ignored, the existence of these risks should be told to pregnant women and their relatives when conducting genetic counseling.