6047例高龄孕妇胎儿染色体核型结果分析

Karyotype Analysis of Fetal Karyotype in 6047 Cases of Advanced Maternal Age

目的:分析高龄孕妇中不同年龄阶段及其他高危因素孕妇发生胎儿染色体异常的特点,以探讨针对单一年龄因素高龄孕妇的产前筛查及诊断策略。方法:本研究收集近三年在首都医科大学附属北京妇产医院产前诊断中心进行产前诊断的高龄孕妇(预产期年龄≥35岁)的临床资料,共6047例,分为4组:A组预产期年龄≤40岁,无其他高危因素;B组预产期年龄≤40岁,存在其他高危因素;C组预产期年龄>40岁,无其他高危因素;D组预产期年龄>40岁,存在其他高危因素。针对胎儿染色体核型分析结果进行回顾性研究。结果:①胎儿染色体异常的总发生率为6.10%,其中非整倍体为4.10%[21三体综合征(T21)为2.30%,18三体综合征(T18)为0.79%,性染色体数目异常为0.94%,13三体综合征(T13)为0.07%],染色体结构异常为1.97%。②A组染色体非整倍体异常(包括T21、T18、性染色体数目异常)及染色体结构异常与B组比较差异均有统计学意义(P<0.01,P<0.05);A组与C组的T21、T18、性染色体数目异常比较,差异有统计学意义(P<0.01,P<0.05),两组染色体结构异常发生率比较差异无统计学意义(P>0.05);B组与D组的T21、T18、性染色体数目异常、染色体结构异常发生率差异无统计学意义(P>0.05);C组与D组的T18、性染色体数目异常、染色体结构异常发生率差异无统计学意义(P>0.05),两组间T21发生率差异有统计学意义(P<0.05)。③单纯高龄因素的孕妇与非单纯高龄因素的孕妇比较,胎儿染色体异常的发生率前者明显低于后者,其发生率随着年龄的增加而呈现逐渐交汇的趋势;而胎儿染色体结构异常的发生率比较,两组间差异无统计学意义。结论:当存在单独年龄因素时,预产期年龄≤40岁的孕妇,其发生胎儿非整倍体异常的风险显著低于预产期年龄>40岁的孕妇,也低于具有其他产前诊断高危因素的人群,采用恰当的产前筛查技术有助于提高此类人群的产前诊断效率。

Objective：To analyze the characteristics of fetal chromosomal abnormalities in advanced maternal age and other high-risk factors. Methods：The prenatal diagnosis data of 6047 pregnant women with advanced maternal age（expected date of age≥35 years old） were collected in Beijing Obstetrics and Gynecology Hospital, Capital Medical University,in the nearly 3 years. All cases were divided into 4 groups according to the expected date of childbirth age （ Group A,35 ≤ age ≤ 40 years old, without other high-risk factors. Group B, 35 ≤ age ≤ 40 years old,with other high-risk factors. Group C,age 〉40 years old,without other high-risk factors. Group D,age 〉 40 years old,with other high-risk factors）,and all the results of fetal karyotype were retrospectively studied. Results ：①Among all cases, the incidence of fetal chromosomal abnormality was 6. 10%, aneuploidy was 4.10% （Trisomy 21 was 2.30% ,Trisomy 18 was 0.79%, numerical sex chromosome abnormality was 0.94%, Trisomy 13 was 0.07% ）, abnormal structure aberration was 1.97%. ②There was significant difference （ P 〈 0.05） of the incidence of fetal aneuploidy,including Trisomy 21 ,Trisomy 18 and numerical sex chromosome abnormalities, and abnormal structure aberration between Group A and Group B. There was significant difference （ P 〈 0.01, P 〈 0.05） of the incidence of fetal aneuploidy,including Trisomy 21 ,Trisomy 18 and numerical sex chromosome abnormalities between Group A and Group C,not in abnormal structure aberration（P〉0.05）. There was no signifi- cant difference （P 〉 0.05） of the incidence of fetal aneuploidy, including Trisomy 21, Trisomy 18 and numerical sex chromosome abnormalities, and abnormal structure aberration between Group B and Group D. There was sig- nificant difference （P 〈 0.01, P 〈0.05） of the incidence of fetal Trisomy 21 between Group C and Group D, but not in aneuploidy, including Trisomy 18 and numerical sex chromosome abnormalities, and abnormal structure ab- erration between two groups （ P 〉 0.05）. ③The incidence of fetal chromosomal abnormalities of pregnant women who were elder than 35 years with the only risk of advanced maternal age was lower than others with another high-risk factors. The risk curve increases with age gradually, with the trend of convergent. There was no signifi- cant difference of the risk of chromosome abnormal structure aberration between them. Conclusions：The incidence of aneuploidy of women with the only risk of advanced maternal age who were younger than 40 years old is lower than other high-risks groups and elder group with single advanced maternal age. It＇s helpful to improve the efficiency of prenatal diagnosis with appropriate prenatal screening in these people.