产前筛查、无创DNA产前检测与改良的羊水产前诊断比较分析

Comparative analysis on prenatal screening,non-invasive prenatal DNA detection,and improved amniotic fluid prenatal diagnosis

目的探讨血清学产前筛查、无创DNA产前检测与改良的羊水产前诊断3种方法在常见的染色体非整倍体疾病方面的临床应用价值。方法首先利用联合血清学筛查检测孕妇血清中的甲胎蛋白(AFP)和游离绒毛膜促性腺素(HCG)β亚基的水平,结合孕妇年龄、孕周、体重等因素,通过Life-Cycle3.2软件计算得出风险系数;筛查高风险孕妇再抽取静脉血,利用无创DNA产前检测方法检测3条染色体(21、18、13)是否有数目异常;对于结果异常的孕妇进一步做改良的羊水产前诊断,以核实无创检测结果的准确性。结果 3557例孕妇中,血清学产前筛查高风险孕妇178例,阳性率为5.00%,其中21-三体和18-三体高风险孕妇共158例;ONTD高风险孕妇20例,阳性率为0.56%。筛查出的21-三体和18-三体高风险孕妇进行无创DNA产前检测,阳性结果为8例,占筛查阳性的比率为4.49%;这8例孕妇均行改良的羊水产前诊断,结果胎儿染色体均为非整倍体,证实21-三体、18-三体和13-三体的符合率均为100.00%。结论无创DNA产前检测可以作为产前诊断21-三体、18-三体和13-三体3种染色体非整倍体疾病的首选,该技术大大减少了侵入性的产前诊断技术对胎儿和孕妇的创伤,是今后发展的必然趋势。

Objective To explore the clinical application value of serological prenatal screening, non-invasive prenatal DNA detection, and improved amniotic fluid prenatal diagnosis for common chromosomal aneuploidy diseases. Methods Serological screening was used to detect the levels of alpha fetoprotein （AFP） and free human chorionic gonadotropin in beta subunit （β-hCG） in serum of pregnant women, combining with the age, gestational weeks, and weight of pregnant women, Life-Cycle 3.2 software was used to calculate risk coefficient; high-risk pregnant women were screened, and venous blood specimens were abstracted, non-invasive prenatal DNA detection was used to detect the numbers of three chromosomes including 21, 18, and 13. Improved amniotic fluid prenatal diagnosis was performed among the pregnant women with abnormal results to check the accuracy of non-invasive prenatal DNA detection. Results Among 3 557 pregnant women, 178 high-risk pregnant women were screened by serological screening, the positive rate was 5.00% , 158 pregnant women were high-risk pregnant women of trisomy 21 syndrome and trisomy 18 syndrome; 20 pregnant women were high-risk pregnant women of ONTD, the positive rate was 0. 56%. The high-risk pregnant women of trisomy 21 syndrome and trisomy 18 syndrome were detected by non-invasive prenatal DNA detection, eight pregnant women were positive, accounting for 4.49% ; all the eight pregnant women received improved amniotic fluid prenatal diagnosis, all the fetuses were aneuploidy, the coincidence rates of trisomy 21 syndrome, trisomy 18 syndrome, and trisomy 13 syndrome were 100. 00%. Conclusion Non-invasive prenatal DNA detection can be used as the first choice in diagnosis of 21 syndrome, trisomy 18 syndrome, and trisomy 13 syndrome, and it greatly reduces the wound of invasive prenatal diagnosis to fetuses and preg- nant women, which will be the inevitable trend of future development.