无创产前检测筛查胎儿性染色体变异的价值OA

Objective To explore the clinical screening efficacy and application value of noninvasive prenatal testing(NIPT)for fetal sex chromosome variations.Methods A retrospective analysis was conducted on the NIPT results of 38 034 singleton pregnancies at the prenatal diagnosis center of the first people's hospital of Chenzhou from January 2021 to December 2024.For those with positive fetal sex chromosome variations indicated by NIPT,peripheral blood karyotype analysis,amniotic fluid karyotype analysis,and copy number variation sequencing(CNV-seq)were performed for verification.The positive rate of screening in each group was compared using χ2 test,and independent influencing factors of fetal sex chromosome aneuploidy abnormalities(SCAs)were analyzed using multivariate Logistic regression.Results 154 cases of chromosomal aneuploidy(SCAs)were detected by NIPT,with a detection rate of 0.41％.Compared with the<35 years old group,the detection rate of fetal SCAs in the≥35 years old group was higher,and the difference was statistically significant(χ2=12.86,P<0.05);after adjusting for confounding factors,being≥35 years old for the pregnant woman was an independent risk factor for fetal SCAs(OR=1.77,95％CI:1.30-2.41,P<0.05);the overall positive predictive value(PPV)of NIPT for SCAs was 50.00％,and the PPV of the four types of SCAs karyotypes was as follows:47,XXY(83.33％),47,XXX(66.67％),47,XYY(55.56％),45,X(33.33％).Among the 59 cases with confirmed chromosomal variations(including 2 cases inconsistent with the NIPT indication),the induction rate was 52.54％(31/59),and all 55 NIPT false positive cases delivered full-term babies.No abnormalities were found in the newborn follow-up.Conclusion NIPT has reliable clinical application value for screening fetal SCAs.Combined with amniotic fluid karyotype and CNV-seq,it can clearly diagnose chromosomal variations,providing a basis for clinical genetic counseling and pregnancy management.