Nuclei size in relation to nuclear status and aneuploidy rate for 13 chromosomes in donated four cells embryos

Purpose The aim was to elucidate if the nuclear size and number are indicative of aberrant chromosome content in human blastomeres and embryos. Methods The number of nuclei and the nucleus and blastomere size were measured by a computer controlled system for multilevel analysis. Then the nuclei were enumerated for 13 chromosomes by a combination of PNA and DNA probes. Results In the mononucleated embryos there was no difference in the mean size of chromosomally normal and abnormal nuclei but a significant difference in the mean nuclei size of nuclei that had gained chromosomes compared to nuclei that had lost chromosomes. The nuclei from multinucleated blastomeres had a significant smaller mean size and the frequency of chromosomally aberrant blastomeres was significantly higher. Conclusion The mean nuclear size is not a marker for the chromosome content in mononucleated embryos. However, it seems that the nuclei size can be related to multinucleation and maybe to the chromosome content.