Objective Exploring the clinical significance of further non-invasive genetic testing(NIPT)for patients with low-risk Down's syndrome but abnormal MOM values in prenatal screening.Methods Time resolved fluorescence immunoassay was used to detect the levels of free chorionic gonadotropin(freeβ-hCG)and pregnancy associated plasma protein-A(PAPP-A)in the serum of pregnant women during early pregnancy,as well as the levels of alpha fetoprotein(AFP),free β-hCG,and free estriol(uE3)in the serum of pregnant women during mid pregnancy,combined with the information of pregnant women's personal factors such as gestational week,age,weight,smoking history,diabetes history,adverse pregnancy and childbirth history,and through the calculation of the risk software LifeCycle,the NIPT results of pregnant women with abnormal MOM values in Down's screening single index were tracked.Those with abnormal NIPT results were subjected to amniocentesis,and the amniocentesis results were taken as the gold standard to analyze its significance.Results From May 2021 to May 2024,a total of 76048 pregnant women underwent Down syndrome screening.Among them,4964 cases(6.5％)had abnormal MOM values in the single indicator of Down syndrome screening.Among them,2846 cases(57.33％)agreed to undergo NIPT testing,and 19 cases(0.67％)had abnormal NIPT results.All pregnant women with NIPT abnormalities underwent amniocentesis.Among them,14 cases had normal chromosome karyotyping analysis,short tandem repeat(STR)and chromosomal microarray analysis(CMA),and 5 cases had chromosomal abnormalities,including 4 cases of trisomy 21 and 1 case of microduplication on chromosome 21,with a fragment size of about 4.46 MB.Conclusion When screening for low-risk Down syndrome,abnormal MOM values in a single indicator can also screen for fetuses with chromosomal abnormalities.Doctors should fully inform them of the limitations of Down syndrome screening and recommend NIPT testing.Although the risk value of Down syndrome screening is calculated by integrating various risk parameters,while the risk value is important,the detection significance of a single serological marker cannot be ignored.Especially for pregnant women with low PAPP-A MOM,even if the fetal chromosomes are not abnormal,they still have a high incidence of adverse pregnancy and should be given sufficient attention.
关键词
唐氏综合征/MOM值异常/无创产前检测
Key words
Down's syndrome/MOM value abnormal/Non-invasive Prenatal Testing
维普
万方数据