The yield of chromosomal microarray analysis among pregnancies terminated due to fetal malformations

Abstract

Background Chromosomal microarray analysis (CMA) is preferred for genetic work-up when fetal malformations are detected prenatally. Objectives To assess the detection rate of CMA after pregnancy termination due to abnormal ultrasound findings. Methods CMA was successfully performed in 71 pregnancies using fetal DNA (mainly from skin) or placenta. Data regarding clinical background, pregnancy work-up, and CMA were analyzed. Results Findings were abnormal in 17 cases (23.9%), of which 13 were detectable by karyotype. The incremental yield of CMA was 4/71 (5.6%); 1/32 (3.1%) for cases with an isolated anomaly and 3/39 (7.7%) for cases with nonisolated anomalies. Conclusions CMA yield from terminated pregnancies was 23.9%. Although most chromosomal abnormalities are detectable by karyotype, CMA does not require viable dividing cells; hence, it is more practical for work-up after termination. In most cases, the diagnosis was followed by consultation regarding the risk of recurrence and recommendations for testing in subsequent pregnancies.