Slabbert, MarisaDu Plessis, S.S.Huyser, Carin2015-12-142015-06Slabbert, M, Du Plessis, SS & Huyser, C 2015, 'Large volume cryoprotectant-free vitrification : an alternative to conventional cryopreservation for human spermatozoa', Andrologia, vol. 47, no. 5, pp. 594-599.0303-4569 (print)1439-0272 (online)10.1111/and.12307http://hdl.handle.net/2263/51156Vitrification is a simple and cost-effective method for the storage of human spermatozoa without the use of conventional cryoprotectants, by plunging the sperm suspension directly into liquid nitrogen. As a result, solidification of living cells without the formation of ice crystals is achieved during cooling. This study aimed to compare cryoprotectant-free vitrification to conventional cryopreservation protocols. Semen samples (n = 35) were collected from patients seeking diagnostic assistance at the Reproductive and Endocrine Unit at Steve Biko Academic Hospital. Samples were processed using a discontinu-ous density-gradient centrifugation method. Washed samples were split into two aliquots and cryopreserved either by means of cryoprotectant-free vitrifica-tion (sucrose + 1% albumin) or conventional slow freezing (TEST-yolk buf-fer). Post-thawing, the sperm motion parameters, mitochondrial membrane potential (Dwm) and DNA fragmentation were compared between the two groups. No significant differences were observed in the sperm motility parame-ters (P > 0.05). Significantly higher percentages of Dwm (11.99% 4.326%versus 6.58% 1.026%; P < 0.001) and lower percentages of DNA fragmenta-tion (2.79% 1.017% versus 3.86% 1.38%; P < 0.01) were observed when comparing cryoprotectant-free vitrification to conventional cryopreservation. Cryoprotectant-free vitrification is a rapid and promising alternative to conventional methods resulting in good-quality spermatozoa post-thaw.en© 2014 Blackwell Verlag GmbH. This is the pre-peer reviewed version of the following article : Large volume cryoprotectant-free vitrification : an alternative to conventional cryopreservation for human spermatozoa, Andrologia, vol. 47, no. 5, pp. 594-599, 2015. doi : 10.1111/and.12307. The definite version is available at : http://onlinelibrary.wiley.comjournal/10.1111/(ISSN)1439-0272.CryopreservationDNA integrityHuman spermatozoaMitochondrial membrane potentialVitrificationDeoxyribonucleic acid (DNA)Postprint Article