Array comparative genomic hybridization profiling of first-trimester spontaneous abortions that fail to grow in vitro.

Objectives: Cytogenetic analysis of spontaneous abortion samples can be limited by culture failure. Failure to grow in vitro has traditionally been suspected to be due to in vivo death of tissue associated with spontaneous abortion (SAB) or simply technical factors of growth in culture.

Method: We used array comparative genomic hybridization (array CGH) to investigate chromosomal imbalances in products of conception that failed to grow in vitro.

Results: Our data on 26 cases of SABs that failed to grow in culture are compared and contrasted with published data on cytogenetic findings following in vitro culture. The results revealed abnormalities uncommonly seen by classic cytogenetic methods. These abnormalities include high rates of double aneuploidy and autosomal monosomy. The data taken together suggest that classic cytogenetics of spontaneous abortion may yield normal karyotypes or selected abnormal karyotypes that permit cell proliferation in vitro while Array CGH detects other abnormalities.

Conclusion: Array CGH is becoming an important clinical assay for unbalanced chromosome abnormalities whether cells grow in culture or not and in cases of analysis on one or few cells.