Chromosome karyotype analysis in 3226 cases with prenatal diagnosis indication

Objective To investigate the relationship between different prenatal diagnostic indications and fetal abnormal karyotypes. Methods The amniotic fluids or cord bloods were collected in 3 226 pregnant women with prenatal diagnosis indications in our center from 2014 to 2018.The chromosomal karyotypes and the abnormal chromosomal karyotype detection rate were analyzed. Results A total of 289 fetal chromosomal abnormalities(excluding chromosomal polymorphisms)were detected in 3 226 karyotypes,with detection rate of 8.96%.The abnormal karyotype detection rates in single indication group,two indications group and three indications group were 6.81%,38.57%,and 75.00% respectively,with statistically significant differences between these groups(P<0.05,respectively).The abnormal karyotype detection rate in NIPT-positive subgroup(56.38%)was the highest in the single indication group,followed by the parental chromosomal abnormality subgroup(52.78%). Conclusion The abnormal chromosomal karyotype detection rate of NIPT-positive group and parental chromosomal abnormalities group ranks highest in all the indications.Pregnant women with more prenatal diagnosis indications have higher risk of fetal chromosomal abnormalities.