EFFECT OF PENTOXIFYLLINE ADDED TO FREEZING MEDIA ON SUBSEQUENT POSTTHAW HYPOOSMOTIC SWELLING TEST AND OTHER SEMEN PARAMETERS

This study evaluated the effects of pentoxifylline (PTX) on post-thaw semen parameters as well as the hypoosmotic swelling (HOS) test. Fourt een samples were evaluated for volume, count, motility, % grade A sper m, and HOS test. Two aliquots were frozen, one in freezing medium and the other in a 3 mM solution of PTX and freezing medium. Both groups w ere frozen in liquid nitrogen vapors for 30 min. Thawing was performed at 37 degrees C for 15 min, followed by a wash with 2 parts 0.5% HSA/ MHTF to 1 part sample. Pellets were resuspended in 0. MHTF and then ev aluated as described above. In addition, motility was evaluated 2 h po st-thaw. Following freeze-thaw, the mean motile densities were similar (17.5 x 10 motile/mL vs. 20.4 x 10(6) motile/mL for PTX and control, respectively). Two hours post-thaw, the PTX group had a mean sperm mot ility of 31.3% vs. 37.7% for the control group (p > .05). There were n o significant differences in % grade A sperm in PTX (43.0%) vs. contro l (12.0%). Similarly, HOS scores did not improve following cryopreserv ation (43.0% and 50.6% for PTX and control, respectively). Thus, no im provement was found by freezing sperm with PTX.