Supplementation of biotin to sperm preparation medium increases the motility and longevity in cryopreserved human spermatozoa.

PURPOSE: To study the effect of supplementing biotin to sperm preparation medium on the motility of frozen-thawed spermatozoa. METHODS: Semen samples of men attending the University infertility clinic (n = 105) were cryopreserved using glycerol-egg yolk-citrate buffered cryoprotective medium in liquid nitrogen. After a period of two weeks, the semen samples were thawed and the motile spermatozoa were extracted by swim-up technique using Earle's balanced salt solution (EBSS) medium supplemented with either biotin (10 nM) or pentoxifylline (1 mM). The post-wash motility was observed up to 4 h after incubation. RESULTS: Both biotin and pentoxifylline supplementation resulted in significant increase in total motility (p < 0.05), progressive motility (p < 0.001) and rapid progressive motility (p < 0.05 v/s biotin and p < 0.01 v/s pentoxifylline) compared to the control at 1 h post-incubation period. Significantly higher percentage of total (p < 0.01, p < 0.05 in biotin and pentoxifylline respectively), progressive (p < 0.001) and rapid progressive motilities (p < 0.01) were observed in these two groups even at 2 h compared to the control. In the control group at 4 h after incubation, ~11% decline in total motility and ~8% decline in progressive motility was observed. However, in both biotin and pentoxifylline group the motility was significantly higher than control (p < 0.001). No significant difference in the motility was observed between biotin and pentoxifylline groups at any of the time intervals studied. CONCLUSIONS: Biotin can enhance the sperm motility and prolong the survival of frozen-thawed semen samples which may have potential benefit in assisted reproductive technology field.