Figure 2. Total levels of PLCζ per spermatozoon (fluorescence intensity, arbitrary units), as mean ± SEM, in fertile controls and infertile patients less than 40 years of age, or equal to and older than 40 years of age.

Different letters in superscript (a,b) denote significant (P < 0.05) differences between controls, patients and age groups. Fertile controls presented significantly higher proportions of sperm exhibiting PLCζ than patients, but no significant differences were found in relation to male age.