Impact of Post-Thaw Incubation Time of Frozen Embryos on Clinical Pregnancy Rate.

Background: Vitrification of embryos following a single-controlled ovarian stimulation has been the strategy practised now in many fertilisation clinics to minimise the risk of early ovarian hyper stimulation syndrome, to reduce multiple pregnancy rates and to improve cumulative pregnancy rates. In recent years, advances in vitrification techniques and improved culture conditions have led to good post-thaw embryo survival rates, thereby increasing pregnancy rates of frozen embryo transfer (FET) cycles.

Aim: The aim of this study was to analyse the effect of post-thaw incubation time of frozen embryos on the clinical pregnancy rates (CPRs) of frozen embryo transfer (FET) cycles.

Mitochondrial DNA Levels in Trophectodermal Cells Show No Association with Blastocyst Development and Pregnancy Outcomes.

Background: In patients undergoing assisted reproduction, levels of mitochondrial DNA (mtDNA) in the trophectodermal cells of the developing blastocyst are suggested to be associated with its ability to implant. However, discrepancies exist regarding the use of mtDNA levels as a reliable biomarker to predict outcomes of assisted reproduction.

Aims: The aim of the study is to explore the association of trophectodermal mtDNA levels to determine blastocyst quality, implantation potential of blastocyst and clinical outcomes in couples who have undergone pre-implantation genetic testing for aneuploidy (PGT-A).