Human Sperm Vitrification: Review of Recent Progress

Sperm vitrification has been used in the field of assisted reproductive technology (ART) for years and has resulted in many healthy live births. Compared to the conventional sperm slow freezing method, vitrification is simpler, quicker, and less expensive, and some vitrification methods are also cryoprotectant free, which has the potential to become an alternative cryopreservation method for human sperm. Human sperm vitrification has been the most commonly used and valuable way to preserve the fertility of males with small numbers of spermatozoa. Recently, new sperm vitrification devices have been developed to help improve volume control. Direct contact during the vitrification process with liquid nitrogen increases the risk of cross-contamination. New strategies have been implemented to minimize the contamination risk. Depending on the variety of semen parameters and patients’ purposes at ART clinics, specific sperm cryopreservation approaches should be personalized to achieve the optimal results for each case.