Components of a Semen Analysis
A standard semen analysis includes seven key parameters: ejaculate volume, pH, sperm concentration, total sperm number, motility, forward progression, and morphology. 1
Standard Parameters and Reference Values
According to the 2024 AUA/ASRM guidelines, a comprehensive semen analysis includes:
- Semen Volume: Lower reference limit of 1.4 mL (1.3-1.5 mL) 1
- Total Sperm Number: Lower reference limit of 39 million per ejaculate (35-40 million) 1
- Sperm Concentration: Lower reference limit of 16 million/mL (15-18 million/mL) 1
- Sperm Vitality: Lower reference limit of 54% live spermatozoa (50-56%) 1
- Progressive Motility: Lower reference limit of 30% (29-31%) 1
- Total Motility (Progressive + Non-Progressive): Lower reference limit of 42% (40-43%) 1
- Morphologically Normal Forms: Lower reference limit of 4.0% (3.9-4.0%) 1
- pH: Should be greater than 7.2 1
Collection and Handling Requirements
Proper collection and handling are critical for accurate results:
- Abstinence period: Patients should abstain from sexual activity for 2-3 days before collection 1
- Collection methods: Masturbation or intercourse using specialized semen collection condoms 1
- Transport conditions: If collected at home, specimen should be kept at room or body temperature 1
- Time constraints: Examination should occur within one hour of collection 1
Clinical Interpretation and Additional Testing
Abnormal results may warrant further investigation:
- Low volume ejaculate (<1.4 mL) with acidic pH (<7.0) suggests ejaculatory duct obstruction or absence of seminal vesicles 1
- Azoospermia (absence of sperm) requires differentiation between obstructive and non-obstructive causes 1
- Severe oligospermia (<5 million/mL) may warrant genetic testing including karyotype and Y-chromosome microdeletion analysis 1
- Post-ejaculatory urinalysis should be performed if ejaculate volume is less than 1 mL to rule out retrograde ejaculation 1
Frequency of Testing
- The 2024 AUA/ASRM guidelines support that a single properly performed semen analysis is often sufficient for initial evaluation 1
- However, if abnormalities are detected, a second confirmatory analysis should be performed at least one month after the first 1
- This represents a change from previous recommendations that routinely required two separate analyses 1
Additional Specialized Tests
While not part of routine analysis, these may be ordered in specific circumstances:
- Fructose testing: Can help identify seminal vesicle dysfunction or ejaculatory duct obstruction, though considered relatively unreliable 1
- Leukocyte assessment (Endtz test): To identify potential infection or inflammation 2
- Sperm antibody testing: For suspected immunological infertility 1
Common Pitfalls to Avoid
- Inadequate abstinence period: Can significantly affect volume and concentration 1
- Improper collection technique: Partial sample loss can invalidate results 1
- Delayed analysis: Affects motility assessment 1
- Failure to follow WHO standardized procedures: Leads to high variability between laboratories 1
- Over-reliance on a single parameter: The entire profile should be considered when evaluating fertility potential 1