Fluorescentin situhybridization (FISH) on paraffin-embedded placental tissues as an adjunct for understanding the etiology of early spontaneous abortion

Abstract

An investigation of first-trimester spontaneous abortions (SAs) for those cases in which karyotype is not available was designed to test the efficiency of fluorescence in situ hybridization (FISH) on paraffin-embedded tissues combined with pathological examination for understanding the etiology of SAs. Pathological examination of 202 placental tissues from SAs was performed. FISH analysis was then carried out on paraffin-embedded tissue sections from the same abortion products with probes specific for chromosomes 13, 16, 18, 21, X, Y. FISH could be achieved in 196 cases (97%). After pathological analysis alone, the etiology of SAs was evoked in 40 cases. The suspected diagnosis was confirmed by FISH in 26 cases (13.2%). After combined pathological and FISH analysis, the etiology of SAs was identified in 83 from the 196 cases (42.3%) with the probe set used. The present study demonstrates the value of FISH on paraffin-embedded tissues as an adjunct for understanding the etiology of SAs for those cases in which karyotype is not available. Combination of pathological and FISH analysis increases the yield of diagnosis by a factor of 3.2. The results also demonstrate that predictions of the karyotype from pathological examination should be avoided.