Characteristic analysis of prenatal diagnosis of fetal chromosomal abnormality in elderly pregnant women
Liu Heng, Guo Wanru, Jiang Tiancong, et al
Prenatal Diagnosis Genetic Diagnosis Center, Tangshan Maternal and Child Health Hospital, Tangshan Key Laboratory of Birth Defect Screening and Diagnosis, Hebei, Tangshan 063000, China
Abstract: 【Abstract】 Objective To analyze the characteristics of fetal chromosome abnormal results in interventional prenatal diagnosis of elderly pregnant women. Method A total of 638 elderly pregnant women who underwent amniocentesis at the Prenatal Diagnosis Genetic Diagnosis Center, Tangshan Maternal and Child Health Hospital from January 2020 to June 2023 were retrospectively selected as the study objects. According to the expected age of the pregnant women, they were divided into group A (35-<40 years,n=463) and group B (≥40 years, n=175). The results of chromosome karyotype analysis and copy numbervariation sequencing (CNV-seq) detection in amniotic fluid cells of elderly pregnant women were analyzed.Statistical methods performed by χ2 test. Result Among the 638 elderly pregnant women, the detectionrate of abnormal chromosome karyotype in amniotic fluid cells was 8.3% (53/638), and the detection rate in group A and group B was 6.9% (32/463) and 12.0% (21/175), respectively. The detection rate in group Bwas higher than that in group A (χ2=15.241, P<0.05). CNV-seq test results showed that the detection rate ofabnormal copy number variation (CNV) in amniotic fluid cells was 10.2% (65/638), and the detection rate ingroup A and group B was 8.9% (41/463) and 13.7% (24/175), respectively. The detection rate in group B washigher than that in group A (χ2=13.634, P<0.05). Conclusion The incidence rate of fetal chromosomalabnormalities increases significantly with the age of elderly pregnant women. The chromosome karyotype analysis and CNV-seq test of amniotic fluid cells in elderly pregnant women can further improve the detection rate of chromosome abnormalities in elderly pregnant women.