PERCENTAGE OF NORMAL SPERM HEADS IS SIGNIFICANTLY INCREASED BY PERCOLL SEPARATION OF SEMEN

The purpose of this study was to assess objectively the effects of Per coll separation on human sperm head morphometry. Semen samples were wa shed and smears were prepared on slides. An aliquot of each sample was centrifuged on a Percoll gradient and spermatozoa were prepared on sl ides. Dimensions of sperm heads from each sample were assessed by comp uter-aided sperm head morphometry analysis and manual sperm morphology was assessed for each sample. The percentage of normal sperm heads an d morphometric dimensions from washed and post-Percoll separated sampl es were compared across all men by a paired t-test. Correlations betwe en normal sperm head morphometry and manual sperm morphology were asse ssed in washed and Percoll-separated samples. The percentage of normal sperm head morphometry was significantly (p < 0.001) higher in Percol l-separated samples than in washed samples (23.6 vs. 12.6%). No differ ences (p > 0.1) in mean sperm head measurements were detected between washed samples and Percoll-separated samples. Coefficients of variatio n for mean sperm head measurements were significantly lower in Percoll -separated samples. No correlation (p > 0.1) in percentage normal was found between computer-assisted sperm head morphometry and manual morp hology for washed and post-Percoll samples. These results indicate tha t percentage normal sperm head morphometry is increased by Percoll sep aration. While sperm head dimensions were unchanged, sample variabilit y was decreased.