Objective: To analyze the impact of maternal age on sex chromosome aneuploidies (SCA).
Methods: Pregnant women who had karyotype analysis of amniotic fluid in Women's Hospital, Zhejiang University School of Medicine from January 2014 to July 2018 were recruited. The association of the maternal age with fetal SCAs was analyzed.
Results: The incidence of 45, X in age group >34-<38 was lower than that of ≤ 28 age group (P<0.05). For the incidences of total sex chromosome trisomy and 47, XXY in age groups 34-<38 and ≥38 were higher than age groups ≤28 and >28-34 (P<0.05 or P<0.01). The incidence of 47, XXX in age group ≥ 38 was higher than that in age group>28-34 (P<0.05). However, the incidence of 47, XYY had no differences among the four groups (P>0.05). After excluding the high risk of sex chromosome abnormalities by non-invasive prenatal testing (NIPT), we found that for 45, X, the incidences of two groups with advanced age were lower than that of ≤ 28 year-old group of age group (P<0.05 or P<0.01), and incidence in age group >34-<38 was also lower than that in age group >28-34 (P<0.05). The other results were consistent with those without excluding the high risk of sex chromosome abnormalities by NIPT.
Conclusions: Advanced age decreases the incidence of 45, X, but increases the risk of sex chromosome trisomy, especially 47, XXX and 47, XXY.
目的: 分析孕妇年龄对胎儿性染色体非整倍体发生风险的影响。
方法: 以2014年1月至2018年7月在浙江大学医学院附属妇产科医院行羊水染色体核型分析的孕妇为研究对象，分为非高龄组（≤28岁、>28~34岁）和高龄组（>34~ < 38岁和≥38岁），比较各组间胎儿性染色体非整倍体的发生率。
结果: > 34~ < 38岁组胎儿45，X的发生率低于≤28岁组（ P < 0.05）；高龄组两个亚组胎儿总的性染色体三体的发生率高于非高龄组的两个亚组（ P < 0.05或 P < 0.01）；≥38岁组47，XXX发生率高于>28~34岁组（ P < 0.05）；高龄两组47，XXY发生率高于非高龄组的两个亚组（ P < 0.01）；各组间胎儿47，XYY发生率差异无统计学意义（ P>0.05）。排除无创产前检测提示性染色体异常高风险孕妇后，高龄组两个亚组胎儿45，X发生率均低于≤28岁组（ P < 0.05或 P < 0.01），且>34~ < 38岁组45，X发生率低于>28~34岁组（ P < 0.05）；其余结果均与全部孕妇结果一致。
结论: 孕妇年龄越大，胎儿45，X发生风险降低，但47，XXX和47，XXY的发生风险升高。