不同指征对高龄孕妇产前诊断胎儿染色体非整倍体的预测价值

Predictive value of different prenatal diagnosis indications for fetal chromosomal aneuploid among advanced maternal age women

目的探讨不同指征对高龄孕妇(advanced maternal age,AMA)产前诊断胎儿染色体非整倍体的预测价值,为AMA遗传咨询提供指导。方法回顾分析我院2008年1月至2013年12月期间AMA产前诊断的记录,计数不同指征行产前诊断的病例数及检出非整倍体数,计算阳性预测值(positive predictive value,PPV),采用行×列表资料的χ2检验比较PPV的差异。结果 2167例AMA行产前诊断共检出非整倍体83例,非整倍体发生率为3.83%(83/2167)。不同指征的PPV(非整倍体数/产前诊断的病例数)如下:高龄为唯一指征0.76%(5/657);夫妇一方染色体异常或不良孕史或致畸因素1.78%(4/225);血清筛查高风险3.21%(37/1152);超声筛查胎儿异常19.8%(18/91);血清筛查高风险伴超声异常45.2%(19/42)。不同指征的PPV的差异有统计学意义(χ2=286.3,P<0.01)。结论对AMA胎儿非整倍体预测价值最高的指征是血清筛查高风险伴超声异常,最低的是高龄为唯一指征,建议对AMA行血清和超声联合筛查使产前诊断指征更加高效明确。

Objective：To calculate the positive predictive value（PPV）for aneuploidies with different prenatal diagnosis indications among advanced maternal age women（AMA）,to guide genetic counseling for AMA. Methods：Retrospective analyzed medical records of AMA underwent amniocentesis in our hospital from January 2008 to december 2013. To calculate the PPV of different diagnosis indications for aneuploidies,compared the difference of the PPV by For× list data Chi-square test. Results：Altogether 83 cases were diagnosed to be aneuploidies among 2167 AMA,the incidence rate were 3.83%（83/2167）,The PPV of different diagnosis indications were below（aneuploidies/ underwent amniocentesis）：AMA alone were 0.76%（5/657）;one of a couple was chromosomal abnormalitie or adverse pregnancy history or teratogenic factors were 1.78%（4/225）;high risk of serum screening were 3.21%（37/1152）;Ultrasound abnormalities were 19.8%（18/91）;high risk of serum screening and Ultrasound abnormalities were 45.2%（19/42）;There were statistical difference between the PPV（χ^2=286.3,P﹤0.01）. Conclusion： The highest PPV was high risk of serum screening and Ultrasound abnormalities,the lowest was AMA alone,AMA should receive serum and Ultrasound combined screening so that prenatal diagnsis indications was more higher and clearer.