[The value of combined use of chromosomal karyotyping and chromosome microarray analysis for prenatal diagnosis]

To assess the value of combined chromosomal karyotyping and chromosomal microarray analysis (CMA) for prenatal diagnosis.

G-banding karyotyping and CMA were simultaneously performed on 546 women who were subjected to amniocentesis during middle pregnancy.

In total 82 cases were detected with chromosomal abnormalities. The two methods were consistent in 43 cases, which included 14 trisomy 21, 6 trisomy 18, 1 trisomy 13, 14 sex chromosomal aneuploidies, 4 chromosomal deletions, 3 chromosomal duplications and 1 sex chromosomal mosaicism. Fifteen fetuses with chromosomal abnormalities detected by CMA were missed by karyotyping analysis, which included 9 microdeletions and 6 microduplications. Sixteen fetuses with chromosomal abnormalities detected by karyotyping analysis were missed by CMA, which included 15 chromosomal translocations and 1 sex chromosomal mosaicism. In 7 cases, the results of karyotyping analysis and CMA were inconsistent. One supernumerary marker chromosome detected by karyotyping analysis was verified by CMA as 9p13.1p21.1 duplication.

Combined chromosomal karyotyping and CMA can significantly improve the detection rate for chromosomal abnormalities, which has a great value for prenatal diagnosis.