Abstract
BackgroundWith the development of whole-genome sequencing, small chromosomal deletions and duplications could be found by NIPT. This study is to evaluate the clinical significance of fetal chromosomal karyotype analysis and chromosomal microarray analysis (CMA) to clarify the clinical significance of 528 cases of high-throughput sequencing noninvasive prenatal screening suggesting high-risk cases. MethodsNon-invasive prenatal screening showed that the fetus 21, 18, 13, sex chromosomes, and other chromosomes are at high risk of aneuploidy and fetal chromosome copy number variations (CNVs) are at high risk, requiring prenatal diagnosis Pregnant women are the research objects. After obtaining informed consent, fetal cells were obtained by amniocentesis or umbilical vein puncture for chromosomal karyotype and CMA analysis. All cases of childbirth were followed up by telephone over a period of 1 year.Results Among 528 fetuses, 447 were at high risk of aneuploidy. The positive predictive value (PPV) for trisomy 21(T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosome aneuploidies (SCAs), and other chromosome aneuploidy was 85.24%, 51.52%, 12.5%, 50.82%, and 5.88% respectively. Another 81 cases of non-invasive prenatal screening suggest CNVs High risk. The PPV for CNVs was 34.57% .Among them, CNVs has a clear pathogenic significance can reach 24.69% . Follow-up of childbirth cases: Of the 62 pregnant women diagnosed with fetal SCA, 13 chose to continue their pregnancy, and the overall continued pregnancy rate was 20.97% (13/62); CNVs has no clear significance/no disease reported in 8 cases, 1 case After being lost to follow-up, all 7 cases chose to continue their pregnancy. One of the children was not informed about the specific situation; one girl had six fingers on both hands, and the rest had no abnormal growth; the remaining five children developed normally. ConclusionThis study has obtained relatively reliable PPV data for NIPT screening for chromosomal aneuploidy, which provides a reliable basis for clinical genetic counseling and treatment; it is recommended to perform prenatal diagnosis and perform chromosomal nucleus when non-invasive and high-risk prompts suspicious chromosomal abnormalities (over/under/microdeletion/microduplication). Type and CMA inspection, so that the inspection is more comprehensive and not easy to miss the diagnosis.
VP30.04: Isolated fetal perigastric echogenic focus on routine prenatal screening ultrasound: prevalence, clinical significance and management considerations
