Melatonin and Caffeine Supplementation Used, Respectively, as Protective and Stimulating Agents in the Cryopreservation of Human Sperm Improves Survival, Viability, and Motility after Thawing compared to Traditional TEST-Yolk Buffer.

Cryopreservation processes can damage spermatozoa and impair structural and functional cell characteristics. Plasma, nuclear membranes, and cellular organelles can suffer from the freeze and thaw process. This study evaluates the protective and stimulant effect of melatonin and caffeine supplementation on the functional characteristics of human spermatozoa before and after freezing.

An easy, reproducible and cost-effective method for andrologists to improve the laboratory diagnosis of nonobstructive azoospermia: a novel microcentrifugation technique.

This study describes a new method of microcentrifugation as an improved, viable, cost-effective option to the classical Cytospin apparatus to confirm azoospermia. Azoospermic semen samples were evaluated for cryptozoospermia by a centrifugation method similar to that of World Health Organization guidelines (2010; entire specimen centrifuged at 3000g for 15 min, and aliquots of the pellet examined). Then, if no sperm were detected, the pellet from that procedure was resuspended in culture medium, centrifuged (2000g for 15 min), and the entire pellet spread on a 4 X 6mm area of a slide and stained using the Christmas tree method (Nuclear-Fast solution and picric acid).