Report of some cases with chromosomal mosaicism in prenatal diagnosis and the corresponding results after birth

Abstract

Chromosomal mosaicism in prenatal diagnosis is a complex problem that confuses the perception of true mosaicism or pseudomosaicismand often causes difficulties in genetic counseling. In this study, the authors reported 5 cases of chromosomal mosaicism in prenatal karyotype diagnosis and compared them with the corresponding karyotype results of children after birth. Amniotic fluid and peripheral blood cells were prepared chromosomal metaphase by culture method and chromosomal analysis according to ISCN 2016 standards. Samples were collected and analysed at Hanoi Medical University Hospital from 2017 to 2020. There were 3 cases of abnormal prenatal chromosomal mosaicism, but the postnatal results were normal, two cases of abnormal prenatal chromosome mosaicism, but had abnormal peripheral blood postnatal chromosome results. These results, together with discussion, will provide more valuable information for the prognosis of chromosome mosaicism cases in prenatal diagnosis and give better genetic counseling for the patients.