Relationship between reactive oxygen species production and lipid peroxidation in human sperm suspensions and their association with sperm function

Objectives: To investigate if reactive oxygen species (ROS) production by human sperm suspensions could predict oxidative stress manifest as lipid peroxidation and if lipid peroxidation was a useful predictor of human sperm function. Design: Laboratory study. Setting: Research laboratory associated with reproductive medicine clinic. Patient(s): Eighty-three couples under evaluation for IVF donated the surplus from a diagnostic semen sample. Intervention(s): Cells were separated from seminal plasma on a 30% Percoll gradient. Main Outcome Measure(s): Reactive oxygen species production, lipid peroxidation, sperm motility measured by computer-assisted semen analysis and ability of the sperm to acrosome react. Result(s): Forty-four samples exhibited ROS production <= 20 000 relative light units (rlu)/s/10(8) sperm and lipid peroxidation <= 40 nmol malondialdehyde/10(8) sperm. The remainder fell into two distinct groups; both exhibited a linear relationship between lipid peroxidation and ROS production but of markedly differing slopes. Abstinence time had no effect. Lipid peroxidation was a good predictor of sperm motility and their ability to acrosome react. Conclusion(s): Reactive oxygen species production in sperm suspensions is an index of overall oxidative stress experienced by sperm, but sperm divide into two classes of ability to resist oxidative stress. Lipid peroxidation should be investigated as a clinical test of sperm function.