Non-invasive mitochondrial DNA quantification on Day 3 predicts blastocyst development: a prospective, blinded,...

Area of Science:

• Reproductive Medicine
• Embryology
• Genetics

Background:

• Embryo quality in assisted reproductive technology (ART) is typically assessed using morphological criteria.
• Previous research indicated a link between the mitochondrial DNA (mtDNA) to genomic DNA (gDNA) ratio in culture medium and embryo quality/viability.

Purpose of the Study:

• To prospectively validate the use of the mtDNA/gDNA ratio in Day 3 spent culture medium as a predictor of human embryo developmental competence.
• To assess if combining mtDNA/gDNA ratio with morphological assessment improves embryo selection.

Main Methods:

• A prospective, blinded, multi-centric study involving 143 patients and 484 Day 3 embryos.
• Quantitative PCR was used to measure the mtDNA/gDNA ratio in spent Day 3 culture media.
• Mixed effect logistic regression models were applied for statistical analysis.

Main Results:

• The mtDNA/gDNA ratio in Day 3 culture medium, when combined with embryo morphology, significantly improved prediction of blastulation compared to morphology alone (P < 0.0001).
• In a separate cohort (44 patients), integrating the mtDNA/gDNA ratio into a grading score increased sensitivity from 92% to 95% and specificity from 13% to 65% for selecting developmentally competent embryos.
• The findings were independent of patient and cycle characteristics.

Conclusions:

• Non-invasive evaluation of embryonic mtDNA content via culture medium is feasible.
• Combining culture medium mtDNA/gDNA ratio with embryo morphology enhances the selection of developmentally competent embryos in ART.
• This approach can aid embryologists in ranking embryos and optimizing embryo transfer decisions.