CORRELATION BETWEEN CELLFREE MITOCHONDRIAL DNA CONTENT OF EMBRYO CULTURE MEDIUM AND HUMAN EMBRYO FRAGMENTATION AND GRADING.

Background: -During In vitro fertilization technology, embryo potential for implantation and successful pregnancy is usually evaluated depending on mostly morphological criteria. Embryo fragmentation is often used as the main criterion for qualifying the human embryo grade and its implantation potential. Fragments of human embryoblastomeres are apoptotic bodies and or anuclear cytoplasmic pieces that release mitochondrial DNA (mtDNA) into the embryo secretome. Cell freemtDNA content of human embryo secretome can be used as a noninvasive tool to evaluate the fragmentation of the embryo cells and thus its grade and implantation potential. Aim: the aim of the present research was to evaluate the correlation between Mitochondrial DNA content of embryo culture medium and human embryo blastomeres fragmentation as an objective noninvasive criterion for embryo quality. Materials and Methods:-50 spent embryo culture mediawere collected from17 Intracytoplasmic sperm injection (ICSI) cycles.After extraction and purification of the free circulating DNA, mitochondrial DNA (mtDNA) was profiled by specific semi quantitative method (Agarose gel electrophoresis).Agarose gel electrophoresis revealed the amplification of the mtDNA from many samples but with different concentrations (the intensity of the bands were vary greatly) and some other samples failed to give a positive amplification. Results: - mtDNA was semi quantified in 50 spent media samples collected from 17 female patients. In 12 samples (24%) mtDNA was undetectable. 6 samples showed mild mtDNA profile, 21 samples with moderate mtDNA profile and 11 samples showed severe mtDNA profile. Insignificant correlation was found between mtDNA profiling in D3 of embryonic development and embryo fragmentation, but when correlating mtDNA profile on D3 and embryo fragmentation and grade; highly significant correlation was found with embryos of G2 or lower quality. Conclusion: -Results of the work shown in the present paper are suggestive of a significant correlation between the human embryo culture media mtDNA content and the degree of embryo blastomeres fragmentation especially in bad quality embryos; that may constitute a promising noninvasive objective criterion for human embryo quality grading and for selecting single embryo transfer policy. - See more at: