Prenatal Utility of Chromosomal Microarray Analysis and Pregnancy Outcomes ： A Cohort Study of 4211 Pregnancies

Abstract

Abstract With the gradual liberalization of the three-child policy and the development of assisted reproductive technology in China, the population of high-risk pregnancies is gradually increasing. In this study, 4,211 pregnant women who underwent chromosomal microarray analysis(CMA) for high-risk indications were analyzed. The results showed that the overall prenatal detection rate of CMA was 11.4%(480/4211), among which the abnormal chromosome number was 5.82%(245/4211), copy number variants༈CNVs༉was 5.58%༈235/4211༉. Additionally, the detection rate of clinically significant copy number variants (CNVs) was 3.78% (235/4211) and 1.8% (76/4211) for variants of uncertain significance. The detection rate of abnormal chromosomes for pregnant women with AMA was 6.42%༈30/467༉, 6.01%༈50/832༉with high-risk MSS, 39.09%༈224/573༉with high-risk NIPT, 9.21%༈127/1379༉with abnormal ultrasound, and 5.1%༈49/960༉ with other indications. During follow-up, of the 4211 fetuses, 3677 fetuses (3677/4211,87.32%) were normal after birth, 462 fetuses (462/4211,10.97%) were terminated pregnancy, 51 (51/4211,1.21%) fetuses were abnormal after birth, and 21 (21/4211,0.50%) fetuses refused follow-up. These findings indicate that the diagnostic rate of CMA varies significantly among different indications, and can serve as a guide for clinicians to evaluate the application range of CMA technology in prenatal diagnosis.