Open AccessThe role of chromosomal microarray analysis among fetuses with normal karyotype and single system anomaly or nonspecific sonographic findings
Author(s) -
Hui Annie Sy,
Chau Matthew Hoi Kin,
Chan Yiu Man,
Cao Ye,
Kwan Angel Hw,
Zhu Xiaofan,
Kwok Yvonne K.,
Chen Zihan,
Lao Terence T.,
Choy Kwong Wai,
Leung Tak Yeung
Publication year - 2021
Publication title -
acta obstetricia et gynecologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 102
eISSN - 1600-0412
pISSN - 0001-6349
DOI - 10.1111/aogs.14003
Subject(s) - cystic hygroma , medicine , fetus , hydrops fetalis , karyotype , microarray , microarray analysis techniques , intrauterine growth restriction , prenatal diagnosis , copy number variation , pathology , obstetrics , chromosome , pregnancy , genetics , biology , gene expression , gene , genome
Chromosomal microarray analysis is recommended as the first‐tier test for the evaluation of fetuses with structural anomalies. This study aims to investigate the incremental diagnostic yield of chromosomal microarray over conventional karyotyping analysis in fetuses with anomalies restricted to one anatomic system and those with nonspecific anomalies detected by sonography. Material and methods This is a retrospective cohort analysis of 749 fetuses undergoing prenatal diagnosis for abnormal ultrasound findings isolated to one anatomic system and normal karyotype, utilizing chromosomal microarray. Overall, 495 (66%) fetuses had anomalies confined to one anatomic system and 254 (34%) had other nonspecific anomalies including increased nuchal translucency (≥3.5 mm), cystic hygroma, intrauterine growth restriction and hydrops fetalis. Results Fetuses with ultrasound anomalies restricted to one anatomic system had a 3.0% risk of carrying a pathogenic copy number variant; the risk varied dependent on the anatomic system affected. Fetuses with confined anomalies of the cardiac system had the highest diagnostic yield at 4.6%, but there were none in the urogenital system. Fetuses with nonspecific ultrasound anomalies had the highest diagnostic yield in fetuses with an intrauterine growth restriction at 5.9%. Overall, fetuses with a nonspecific ultrasound anomaly were affected with pathogenic copy number variants in 1.6% in the cases. Conclusions The diagnostic yield of chromosomal microarray in fetuses with normal karyotype and ultrasound abnormality confined to a single anatomic system was highest if it involved cardiac defects or intrauterine growth restriction. This diagnostic yield ranges from 0% to 4.6% depending on the anatomic system involved. Chromosomal microarray has considerable diagnostic value in these pregnancies.