title: Accessing the fertilizing potential of cryopreserved sperm by its ability to maintain quality in a glycerol-free medium.
abstract: Cryopreserved sperm is less fertile than fresh sperm; probably due to dependence of sperm to glycerol, a common cryoprotective agent. Few data suggest any correlations between standard semen analysis and fertility. To develop a reliable assay, the authors hypothesized that sperm that withstand the physiochemical stress induced by glycerol during cryopreservation may have higher fertility potential. They analyzed 55 cryopreserved semen samples for sperm concentration, percent motility and progressive motility after allowing thawed sperm to migrate into medium containing either 0 or 12% glycerol for 3 h. The smaller the difference in sperm quality between the two media, the higher the fertility potential of the spermatozoa. There was significant negative correlation between the difference in both percent sperm motility and percent progressive sperm motility in the two media and in vitro fertilization outcome. There was a significantly higher number of ejaculates fertilized oocytes at a rate of > or = 80% when the difference was 20% or less. This easy to use, inexpensive test may be an effective means to evaluate the potential performance of cryopreserved sperm to be utilized in assisted reproductive technologies.
authors.affiliation: Department of Obstetrics and Gynecology, Northwestern University Medical School, Chicago, Illinois, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Kolb
authors.forename: V C
authors.initials: VC
authors.lastname: Acosta
authors.forename: R S
authors.initials: RS
authors.lastname: Jeyendran
mesh_terms: D002470:Cell Survival; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000494:pharmacology*; D003470:Culture Media; D005298:Fertility / Q000502:physiology*; D005990:Glycerol / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D012662:Semen Preservation; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology*
chemical_list: D003451:Cryoprotective Agents; D003470:Culture Media; D005990:Glycerol