Cryopreservation of human spermatozoa: comparison of TEST-yolk buffer and glycerol.
OBJECTIVE
Comparison of human sperm motility, morphology, and sperm membrane integrity using two cryoprotective media, Test-yolk buffer with glycerol and glycerol alone.


METHODS
Semen samples from 10 healthy donors were divided and frozen with either glycerol or a combination of glycerol and TEST-yolk buffer. Semen characteristics were evaluated before freezing and after thawing. Motility was measured at 0, 60, 120, and 180 minutes post-thaw following removal of the cryoprotectant (post-wash).


RESULTS
Percentage of motile sperm decreased significantly compared to prefreeze values in both groups. Post-thaw motility following removal of the freezing media was higher in specimens that were frozen in TEST-yolk buffer compared to those frozen in glycerol at 0 minutes (P = 0.004). Similarly, specimens cryopreserved in TEST-yolk buffer had higher sperm motility compared to aliquots that were frozen in glycerol at 180 minutes (P = 0.013). The percentage of normal sperm forms was significantly higher post-wash and post-thaw in specimens that were cryopreserved in TEST-yolk buffer (P = 0.04).


CONCLUSIONS
Sperm cryopreserved in TEST-yolk buffer had significantly better motility, morphology, and sperm membrane integrity than sperm preserved in glycerol alone.
Hallak
J
J
Department of Urology, The Cleveland Clinic Foundation, Ohio 44195, USA.
Sharma
R K
RK
Wellstead
C
C
Agarwal
A
A
D002021:Buffers; D015925:Cryopreservation / Q000379:methods*; D004530:Egg Yolk; D005990:Glycerol; D006801:Humans; D008297:Male; D012662:Semen Preservation / Q000379:methods*; D013094:Spermatozoa / Q000502:physiology
D002021:Buffers; D005990:Glycerol