The Yield of Chromosomal Microarray in Pregnancies Complicated with Fetal Growth Restriction Can Be Predicted According to Clinical Parameters.

INTRODUCTION: We evaluated the yield of chromosomal microarray analysis in pregnancies complicated with fetal growth restriction (FGR) according to specific clinical parameters. METHODS: The study was based on national records from the Israeli Ministry of Health. Chromosomal microarray analyses of amniocenteses performed nationwide for the indication of FGR, from January 2016 to March 2018, were included. The CMA yield was compared to 2 cohorts that reported the background risk. RESULTS: Of 174 tests performed for the indication of FGR, there were 11 cases with a pathogenic/likely pathogenic result (6.3%). The yield of CMA was significantly higher in cases with major structural findings (29.4 vs. 3.4%, p = 0.001), compared to isolated FGR but not for minor structural findings (6.1 vs. 3.4%, p = 0.5). The rate of chromosomal aberrations was significantly higher for all cases with FGR, when compared to the background risk of a cohort of normal pregnancies (odds ratio [OR] 4.7, 95% CI 2.5-9 and OR 6.09, 95% CI 3.2-11.4) but not for isolated cases or cases diagnosed after 24 weeks of pregnancy. CONCLUSIONS: Chromosomal microarray analysis should be performed for all pregnancies complicated with FGR diagnosed before 24 weeks and for cases with major structural anomalies.