Vitrification is a relatively new freezing method commonly used to preserve unfertilized eggs to preserve fertility. Vitrification, unlike other freezing methods, does not produce ice crystals on eggs. Ice crystals have been associated with reduced pregnancy rates or damaged eggs upon thawing. Researchers at the Universite Catholique de Louvain in Belgium recently published a study in the journal Human Reproduction investigating the use of vitrification on male fertility preservation.

For the sake of the study, samples of testicular tissue were frozen using the vitrification process. Ten patients between the ages of two and 12 were included in the study. Preserving the fertility of young male cancer patients was one aim of the study. After being frozen, the tissues were thawed, warmed and xenografted to the scrotum of nude mice. After six months, the seminiferous tubules showed good integrity and researchers were able to initiate sperm production, but there was a blockage in the pachytene stage.

Conclusion: The study pool was limited due to a lack of human samples. Researchers, though able to initiate sperm production, were not convinced vitrification poses a better end result than current freezing techniques used to preserve fertility.

Source: Poels J, Van Langendonckt A, Many MC, Wese FX, Wyns C. Vitrification preserves proliferation capacity in human spermatogonia. Hum Reprod. 2013 Jan 12.