Table 4.

Lower reference limits (5th percentiles and their 95% confidence intervals) for semen parameters [16].

Parameter	Lower Reference Limit
Semen volume (mL)	1.5 (1.4–1.7)
Total sperm number (million per ejaculate)	39 (33–46)
Sperm concentration (million per mL)	15 (12–16)
Total motility (progressive + non-progressive, %)	40 (38–42)
Progressive motility (%)	32 (31–34)
Vitality	58 (55–63)
Sperm morphology (normal forms, %)	4 (3.0–4.0)
Other reference values
pH	≥7.2
Peroxidase-positive leukocytes (million per mL)	<1.0