Comparison of three sperm preparation media.

In assisted reproduction, spermatozoa must be effectively separated from seminal plasma to undergo capacitation, a prerequisite for fertilization. Percoll was recently withdrawn from the American market because of safety concerns. The purpose of this study was to evaluate the quality of sperm separated by two different sperm washing media, and compare these results to sperm quality after separation on a Percoll (Perwash) gradient.Semen samples from 10 normozoospermic men were compared after separation on three media: Perwash, a Percoll-type medium (Conception Technologies, La Jolla, CA), ISolate (Irvine Scientific, Santa Ana, CA), and SpermFertil (Embryotech Laboratories, Wilmington, MA). Semen characteristics examined were: sperm count, percentage motility, curvilinear velocity, lateral head displacement, percentage recovery of motile sperm, viability, hypo-osmotic swelling, and penetration in bovine cervical mucus. Sperm morphology was scored using World Health Organization and Kruger's strict criteria. The motility of the sperm was examined at one-hour intervals for three hours to determine which method produced samples with the longest period of motility.Total motile sperm count, motility, curvilinear velocity, and percentage of normal morphological forms as determined by the WHO method were significantly lower in specimens prepared by SpermFertil than in ISolate or Perwash specimens (P < .05). Tail abnormalities were significantly more frequent in specimens prepared by SpermFertil than in ISolate and Perwash specimens (P < .001). Percentage recovery of motile sperm was significantly higher in ISolate and Perwash specimens than in SpermFertil specimens (P < .05). Semen characteristics were similar in specimens prepared with ISolate and with Perwash. At all time intervals, sperm motility was higher in ISolate and Perwash specimens than in SpermFertil specimens (P < .001).Sperm samples separated with a SpermFertil column have poorer sperm quality in several respects than samples prepared with ISolate or Perwash. This finding and the similarity between ISolate and Percoll procedures suggests that ISolate is a good alternative to Percoll-type media to prepare sperm for assisted reproduction.