Relationship between standard semen parameters, calcium, cholesterol contents, and mitochondrial activity in ejaculated spermatozoa from fertile and infertile males.

Purpose: To correlate levels of cholesterol (CH), calcium (Ca2+), and mitochondrial activity (MA) with the standard semen parameters and to compare them between fertile and infertile men.
Methods: We studied 151 semen samples from infertile (n = 60) or fertile (n = 91) males. Basic sperm parameters were analyzed. Ca2+ and CH concentrations on seminal plasma were determined by enzymoimmunoanalysis. Intracellular Ca2+ and CH concentrations in the sperm plasma membrane and mitochondrial activity by fluorometry.
Results: There was a significant positive correlation between sperm membrane CH and sperm morphology. Intracellular Ca2+ was lower in infertile patients compared to fertile. No differences were found regarding Ca2+ and CH concentrations in seminal plasma. MA is directly and strongly related with sperm motility.
Conclusions: Intracellular concentrations of Ca2+ and the proportion of CH in the sperm membrane are two important markers of the sperm quality due to its direct relationship with sperm morphology and fertility potential.