No association of mitochondrial DNA levels in trophectodermal cells with the developmental competence of the blastocyst and pregnancy outcomes

Abstract

Study questionCan mitochondrial DNA (mtDNA) levels in trophectodermal cells of the blastocyst predict the blastocyst quality, ploidy status, implantation rate and clinical outcomes?\n\nSummary answermtDNA levels in trophectodermal cells of the blastocyst do not associate with the blastocyst quality, ploidy status, implantation potential and clinical outcomes, but can differentiate between aneuploid and euploid blastocysts.\n\nWhat we already knowmtDNA levels in the trophectodermal cells have been suggested to be associated with blastocyst morphology, ploidy and implantation rates, and has been proposed as biomarker to access blastocyst quality and predict clinical outcomes. However, discrepancies exist if mtDNA levels could serve as a marker for the same.\n\nStudy design and durationRetrospective analysis of mtDNA levels in trophectodermal cells obtained from blastocysts undergoing preimplantation genetic testing for aneuploidy (PGT-A) at Craft Hospital & Research Center, Kerala from January 2016-July 2017.\n\nParticipants/materials and methodsStudy included data from 287 blastocyst from (61) couples who underwent PGT-A using next generation sequencing (NGS). Levels of mtDNA in trophectodermal cells of the blastocyst were estimated by the NGS. Comparison of mtDNA levels with maternal age, blastocyst morphology, ploidy status, implantation rates, miscarriage rates and live birth rate was done.\n\nMain resultsThe levels of mtDNA in the trophectoderm of the blastocyst did not correlate with maternal age. There was no significant difference in the mtDNA levels between grade 1 and grade 2 blastocyst. Euploid blastocyst had significantly lower amounts of mtDNA levels in trophectodermal cells of the blastocyst were compared to aneuploid blastocyst. No significant differences were seen between mtDNA levels and implanting and non-implanting blastocysts or those resulted into miscarriage or live birth.\n\nLimitationsThe study is limited by a small sample size and hence type II error cannot be ruled out.\n\nWider ImplicationsThe study does not support the potential use of mtDNA levels in the trophectodermal cells as biomarker for blastocyst quality and predicting clinical outcomes needs.\n\nStudy funding/competing interest(s)There is no external funding for the study. There is no conflict of interest.