The role of mitochondrial activity in female fertility and assisted reproductive technologies: overview and current insights

Mitochondria have been implicated as key factors regulating female reproductive processes. Notable progress has been made in determining the role of mitochondria with respect to oocyte maturation, fertilization and early embryo development. In addition, mitochondrial function and dysfunction has been the subject of various studies in ovarian ageing and metabolic stress models. However, the overall mitochondrial impact on female fertility is yet to be uncovered. The mitochondrial DNA content of granulosa, cumulus and trophectoderm cells is being explored as a biomarker of oocyte quality and embryo viability. As growing evidence suggests that embryo potential could be related to the ability of oocyte mitochondria to generate energy, efforts have been made to investigate the possibility of improving mitochondrial capacity in women with poor outcomes after treatment with assistedreproductive technologies. Thus far, therapeutic attempts have focused mainly on using nutrients to restore mitochondrial function and transferring mitochondria from autologous germline precursor cells. Moreover, new perspectives on optimizing infertility treatments have arisen with modern mitochondrial replacement therapies, which are being applied in women with mitochondrial disease-causing mutations. This review explores aspects of the distinctive contribution of mitochondria to reproductive processes and discusses current and emerging clinical implications.