Chromosome abnormalities in 245 cases of spontaneous abortion

Objective To investigate the effect of maternal age, gestational weeks, numbers of previous spontaneous abortion and embryo gender on chromosomal abnormalities. Methods Bacs on Beads (BoBs) technology was used to detect the chromosome aneuploidy of 245 pregnant women with spontaneous abortion or stillbirth in Jinan Maternity and Child Care Hospital from January 2015 to December 2017 and to analyze the types of their chromosome abnormalities. Comparative analysis between different groups was carried out using Chi-square test. Results Karyotypes of all cases (n=245) were obtained using BoBs. Among them, 113 had chromosome abnormalities (46.1%), including 66 autosomal aneuploidy (58.4%), 26 sex chromosome aneuploidy (23.0%), seven autosomal partial trisomy (6.2%), five autosomal partial monomer (4.4%), seven triploid (6.2%), one complex triploid (0.9%) and one double trisomy (0.9%). Pregnant women aged over 35 had a higher incidence of chromosome abnormality than those under 35 [61.0% (36/59) vs 41.4% (77/186), χ2=8.003, P 0.05). Conclusions Chromosome abnormality is a major cause of spontaneous abortion, particularly in embryos with chromosome aneuploidy, partial trisomy, partial monomer and triploid. Advanced maternal age may increase the risk of chromosome abnormalities in pregnancies complicated with spontaneous abortion or stillbirth. Key words: Abortion, spontaneous; Chromosome aberrations; Chromosomes, artificial, bacterial; Karyotyping