Innovative strategies in sperm cryopreservation: Overcoming challenges and enhancing fertility preservation-A narrative review

Abstract

Sperm cryopreservation is an essential technique for male fertility preservation, especially in men who are undergoing medical treatment. Conventional cryopreservation methods face limitations such as oxidative stress, DNA fragmentation, and cytotoxicity associated with traditional cryoprotectants like dimethyl sulfoxide (DMSO). Recent breakthroughs have focused on improving post-thaw sperm viability with novel cryoprotectants and innovative freezing strategies. Prospective approaches include the use of amino acid-based cryoprotectants, deep eutectic solvents, and antioxidants that have been described to prevent oxidative damage and maintain DNA integrity. Vitrification, a high-speed freezing technique that prevents ice crystal formation, has demonstrated superior outcomes compared to conventional slow freezing. Moreover, the Direct Dropping Method, a cryoprotectant-free approach, has been introduced as a contamination-minimizing technique that preserves sperm functionality. Multiomics tools are also utilized to determine biomarkers for protocol optimization. Despite these advancements, cryoprotectant toxicity is a central challenge, emphasizing the necessity for safer agents. Future research must focus on long-term sperm functionality and individualized cryopreservation strategies to maximize reproductive outcomes. The current review highlights the challenges associated with sperm cryopreservation, explores innovative strategies and novel cryoprotectants, underscores the significance of maintaining DNA integrity, and proposes future research directions to improve fertility preservation outcomes.

Keywords

Assisted reproductive technology / Intracytoplasmic sperm injection / Cryoprotectants / Sperm cryopreservation / Dimethyl sulfoxide

Conflict of interest statement

The authors declare that there is no conflict of interest.

Funding

The study received no extramural funding.

Authors’ contributions

Varaganti Pravardhan contributed to the conception or design of the work, drafting of the work, approval of the final version of the manuscript, and agreed on all aspects of the work. Nancy Nair contributed to the literature review, revision of the manuscript for important intellectual content, approval of the final version of the manuscript, and agreed to all aspects of the work. Varaganti Venkata Sai Suvardhan contributed to the literature review, revision of the manuscript for important intellectual content, approval of the final version of the manuscript, and agreed to all aspects of the work. Trupti Balwir contributed to the review and revision of the manuscript for important intellectual content, approval of the final version of the manuscript, and agreed to all aspects of the work.

Publisher’s Note

The Publisher of the Journal remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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