Application of chromosomal karyotyping analysis and array CGH for fetal abnormalities detected by ultrasonography

Abstract

To assess the value of chromosomal karyotyping and array-based comparative genomic hybridization for the diagnosis of fetus with abnormalities detected by ultrasonography. Umbilical cord blood samples were derived from 1 603 pregnant women. The samples were cultured for routine G-banding karyotype analysis. Among these, 792 samples have further subjected to array CGH analysis. Among the 1 603 fetuses, 117 (7.30%) were found with chromosomal abnormalities. These included 72 numerical aberrations and 45 structural abnormalities, which respectively accounted for 4.49% and 2.81% of all cases. For those <35 years and ≥ 35 years, a significant difference has been found in terms of fetal chromosomal abnormalities (chi-square is 30.687, P< 0.01). And there was also a significant difference between those with isolated, two or multiple ultrasonographic markers (chi-square is 85.50, P< 0.01). Among 736 fetuses with a normal karyotype, array CGH has detected 17 (2.31%) with a microdeletion or microduplication. Karyotype analysis and array CGH should be offered to all fetuses with ultrasonography detected anomalies regardless the number of markers.