Pentoxifylline enhancement of post-thaw motility in cryopreserved semen of spinal cord-injured men.

Objective: To investigate the effects of pentoxifylline on cryopreserved human semen of spinal cord injured men, in efforts to enhance post-thaw motility.
Design: Semen specimens were collected from: pregnancy-proven donors (n = 10), spinal cord injured (SCI) patients (n = 8), and infertility patients referred for white blood cell (WBC) screening of the semen (n = 18). Following at least 24 hours of freezing in 100% tes and tris-yolk buffer, 0.5-mL semen straws were thawed. Each sample was split into two equal aliquots, one of which was treated with 3.6 mM pentoxifylline. Following incubation, percent motility was recorded manually at 15 minutes, 1 hour, 2 hours, and 24 hours post-thaw. Percent original motility preserved (post-thaw motility/original motility X 100%) was calculated for each specimen.
Results: Statistically significant differences (P < .05) were noted in the SCI and WBC patients when samples with and without pentoxifylline were compared at 15 minutes, 1 hour, and 2 hours. No significant difference was noted in the donor population at any time interval, and no difference was seen in any group at 24 hours post-treatment with pentoxifylline. The greatest differential between treatment and control groups was noted at 1 hour in all three populations.
Conclusions: Pentoxifylline enhances post-thaw motility of cryopreserved sperm in male infertility patients from 15 minutes to 2 hours post-treatment. Pentoxifylline appears to be most useful at 1 hour post-treatment in the cryopreserved samples of SCI patients obtained by electroejaculation. It does not appear to have any significant effect on the post-thaw motility of pregnancy- proven donors. Pentoxifylline loses its in vitro efficacy prior to 24 hours post-thaw.