Objective: To correlate the concentration of nitrite (the stable metabolite of nitric oxide) in seminal plasma with sperm number and motility, leukocytospermia, and sperm culture.
Design: Prospective study.
Setting: Academic research institution.
Patient(s): Seventy normozoospermic or dyspermic men enrolled in an artificial insemination/in vitro fertilization program.
Intervention(s): Semen samples (n = 70) were checked for sperm concentration, total sperm count, sperm motility, seminal leukocyte concentration, and sperm culture; similarly, the concentration of nitrite in seminal plasma was measured by Griess reaction.
Main outcome measure(s): Measurement of nitrite concentration in seminal plasma and its correlation with sperm concentration, total sperm count, sperm motility, leukocytospermia, and sperm culture.
Result(s): The concentration of nitrite in seminal plasma does not correlate with sperm concentration, total sperm count, or with the proportion of immotile or rapid-forward motile spermatozoa. Moreover, the concentration of nitrite in seminal plasma is not significantly increased when sperm culture is positive, nor does it correlate with leukocyte concentration in semen.
Conclusion(s): Our results do not support the hypothesis that in vivo nitric oxide synthesis affects sperm function; alternatively, our results could suggest that nitrite in the seminal plasma is not a sensitive marker of in vivo nitric oxide synthesis.