P809: Prenatal chromosomal microarray classification and reporting among screen positive cases in California

In pregnancies with ultrasound anomalies, chromosomal microarray analysis (CMA) can identify key genetic anomalies as well as rarer microdeletions and microduplications not detectable by karyotype. In approximately 6-10% of pregnancies with a fetal structural anomaly, CMA reveals copy number variants (CNVs) that may be clinically relevant yet challenging to classify and interpret. A lack of standardization exists in classification, interpretation and reporting of genetic variants found on prenatal CMA.