Krebs J, Göcking K, Kissling-Niggli M, Pannek J
Clinical Trial Unit, Swiss Paraplegic Centre, Nottwil, Switzerland.
Andrology. 2015 Mar;3(2):213-9. doi: 10.1111/andr.12017. Epub 2015 Feb 13.
The deterioration of semen quality occurs very early after spinal cord injury (SCI). Thus, routine cryopreservation of semen early after injury has been recommended. However, there is currently a lack of data concerning the effects of long-term cryopreservation on the quality of spermatozoa from SCI men. We have therefore investigated the quality of spermatozoa from SCI men before and after long-term cryopreservation. The semen cryobank of a SCI rehabilitation center was screened for samples with a storage duration of more than 3 years, to carry out a cross-sectional study regarding the sperm quality of semen samples from SCI men. Semen quality analysis was carried out according to the WHO-Guidelines. The quality of 28 semen samples from 16 SCI men was investigated prior to and a median 11 years (95% CI 7-13 years) after cryopreservation. Prior to cryopreservation, ejaculate volume (median = 1.7 mL, 95% CI 1-3 mL) and sperm concentration (median = 106 × 10(6) /mL, 95% CI 82-132 × 10(6) /mL) were within normal limits, but total sperm motility (median = 19%, 95% CI 13-22%) and viability (median = 27%, 95% CI 19-45%) were reduced. Cryopreservation resulted in a significant (p < 0.0001) decrease in total sperm motility (median = 2.5%, 95% CI 0-4%) and viability (median = 7%, 95% CI 6-13%). There were no significant (p = 0.75) differences between the semen parameters of samples collected early (up to 3 weeks) after SCI and those collected later. Complete SCI had a significantly (p < 0.0001) negative effect on the sperm viability of the fresh semen samples, and tetraplegia had a significantly (p < 0.035) negative effect on both pre-cryopreservation sperm viability and post-cryopreservation motility. The assisted ejaculation technique had no significant (p > 0.053) effect on semen quality. Long-term cryopreservation of semen from SCI men results in essentially immotile sperm with minimal viability. Thus, routine long-term cryobanking of semen harvested early after SCI cannot be recommended.