Genome copy number variation (CNV) is an important cause of genetic and developmental disorders. In recent years, chromosomal microarray analysis (CMA) technology to test for genomic copy number variation has been developed and gradually applied in prenatal diagnostics, offering high diagnostic ability. Here, the authors summarise the CMA established in clinical settings, as well as the significance and clinical application of the standard analyses. They also emphatically discuss the key problems in the establishment process of the platform in prenatal diagnostics in the clinic.