Epigenetic Stability and Genomic Integrity in Fertility Preservation: Insights from Genetic and Reproductive Technologies

Fertility preservation techniques—particularly cryopreservation and thawing—are essential in reproductive medicine for safeguarding the reproductive potential of individuals facing medical or elective fertility challenges. However, these interventions expose gametes (oocytes and sperm), embryos, and reproductive tissues to physical and molecular stress, potentially compromising both epigenetic stability and genomic integrity. This chapter reviews current knowledge on the maintenance and disruption of DNA methylation patterns, histone modifications, chromatin structure, and non-coding RNA (ncRNA) profiles during storage, alongside potential alterations in nuclear and mitochondrial genomes that may influence developmental competence and transgenerational health. We summarize technological advances in genetic and assisted reproductive technologies, evaluate their impact on molecular integrity, and outline strategies to mitigate damage. Emphasis is placed on the need for standardized protocols, comprehensive genomic and epigenomic assessment, and long-term monitoring to ensure the safety and efficacy of fertility preservation.