Molecular cytogenetic analysis by genomic hybridization to determine the cause of recurrent miscarriage

Cytogenetic and genetic investigation of miscarriage cases in Eastern China

Objective: Recurrent miscarriage (RM) affects about 5% of pregnancies. Etiology of 30-50% RM cases remains unknown. Advanced highly sensitive detection and analysis methods may help solve some of the cases.Methods: Products of conception from 1155 RM cases were analyzed using classic karyotyping. Some cases without abnormal findings were subjected to next generation DNA sequencing (NGS) and chromosome copy number variation (CNV) analysis.Results: Classic karyotyping identified abnormalities in 56.62% of the cases. Of the103 specimens analyzed using NGS, 39 (37.86%) were found to carry "pathogenic" CNVs. Recurrent microdeletions and microduplications were identified, and some with unique distribution patterns.Conclusion: NGS CNV analysis is a highly sensitive and flexible method for detecting genetic abnormalities in RM cases.