Properties of sperm separated using Percoll and IxaPrep density gradients. A comparison made using CASA, longevity, morphology and the acrosome reaction.

Since the withdrawal of Percoll from use in human assisted reproduction techniques in 1996, alternative density gradients have been sought. IxaPrep is one candidate that has low toxicity and can separate spermatozoa. Fractions of spermatozoa from normozoospermic men, separated by Percoll and IxaPrep gradient centrifugation, were assessed for sperm recovery, motility, morphology and the ability to undergo the acrosome reaction. The Percoll fractions had a significantly higher sperm recovery, motile count, rapid motile count, VAP, VSL, and VCL than those obtained using IxaPrep, both immediately after separation and up to 24 h later. In contrast, ALH, level of abnormal sperm morphology and the ability to acrosome react were not statistically different in sperm fractions separated using either gradient forming material.