A semen analysis measures semen volume and several sperm characteristics, including concentration, total sperm number, motility and morphology. It is not a fertility “pass/fail” test. WHO reference limits describe the lower end of values seen in a fertile reference population; results above them do not guarantee pregnancy, and a result below them does not prove infertility. Semen varies naturally from sample to sample, so an abnormal result often needs confirmation and should be interpreted together with the couple’s fertility history, examination and, when appropriate, hormone testing.

Preparation matters

The laboratory usually asks for 2-7 days of ejaculatory abstinence, complete collection into a sterile container and prompt delivery at an appropriate temperature. The first fraction of the ejaculate contains many sperm, so an incomplete sample can falsely lower the count. Fever or significant illness in the previous two to three months can temporarily worsen semen parameters.

WHO 6th-edition lower reference limits

Approximate lower fifth-centile reference values commonly used from the WHO 6th-edition dataset include semen volume 1.4 mL, sperm concentration 16 million/mL, total sperm number 39 million per ejaculate, total motility 42%, progressive motility 30%, vitality 54% live sperm and normal morphology 4% by strict criteria. These are reference limits, not biological borders between fertile and infertile men.

How to read each parameter

Volume

Low volume can result from incomplete collection, short abstinence, retrograde ejaculation, ejaculatory-duct obstruction or androgen deficiency. Very high volume may dilute concentration but total sperm number is more important.

Concentration and total sperm number

Concentration is sperm per mL; total number accounts for the entire ejaculate. A modestly low concentration with good volume can still yield a reasonable total sperm number.

Motility

Progressive motility describes sperm moving forward. Total motility includes progressive and non-progressive movement. Motility is temperature- and time-sensitive, so laboratory handling matters.

Morphology

Strict morphology scores the percentage of sperm meeting very narrow shape criteria. A value around 4% can still be within the WHO lower reference distribution. Morphology has substantial observer variability and should not be interpreted alone.

Vitality

Vitality measures the proportion of live sperm and is particularly useful when motility is very low, helping distinguish immotile live sperm from dead sperm.

Common report labels

• Oligozoospermia: low sperm concentration/number.
• Asthenozoospermia: reduced motility.
• Teratozoospermia: low normal morphology percentage.
• Azoospermia: no sperm seen after appropriate examination; this requires confirmation and evaluation.
• Cryptozoospermia: sperm seen only after concentrated/pellet examination.

When to repeat the test

Because semen varies, one abnormal sample often should be repeated. The timing depends on severity and the clinical question. Very severe abnormalities or azoospermia should prompt specialist evaluation rather than months of unsupervised supplements. If a transient fever likely affected results, a repeat after a spermatogenic cycle may be more informative.

What additional tests may be needed

Depending on the pattern, evaluation may include FSH/LH/testosterone, prolactin, scrotal examination and ultrasound, genetic testing in severe oligozoospermia/azoospermia, assessment for varicocele and review of medicines or testosterone/anabolic steroid exposure. Male and female partners should be assessed in parallel when infertility is the concern.

What not to do after an abnormal report

• Do not start testosterone to “increase sperm”; external testosterone can suppress sperm production.
• Do not judge fertility from morphology alone.
• Do not take months of unproven supplements while ignoring severe abnormalities.
• Do not compare reports from very different abstinence periods without considering collection conditions.

Three rules that prevent over-reading a semen report

First, WHO lower reference limits are not fertile-versus-infertile cutoffs. They describe the lower end of results seen in a reference population of fertile men. Second, semen varies substantially between ejaculates, so an unexpected abnormality usually needs confirmation. Third, fertility is a couple-level outcome: the male report has to be interpreted with duration of infertility and the female partner’s age and fertility evaluation.

Total motile sperm count can be a useful practical summary because it combines volume, concentration and motility, but it still does not replace the full report. Morphology is especially easy to misread: ‘4% normal forms’ does not mean that 96% of sperm are useless or that natural conception is impossible.

How common report labels translate into the next question

Oligozoospermia means low sperm concentration, asthenozoospermia reduced motility and teratozoospermia a low proportion of morphologically normal forms. Oligoasthenoteratozoospermia (OAT) combines abnormalities. Azoospermia means no sperm are seen in the ejaculate after appropriate laboratory assessment; it is not the same as ‘very low count’ and requires a structured evaluation for obstruction versus impaired sperm production.

Very low semen volume raises different questions from low sperm concentration. The clinician may review collection completeness, retrograde ejaculation, ejaculatory-duct obstruction, androgen status and congenital absence of the vas deferens depending on the history. Leukocytes, agglutination or increased viscosity are also secondary clues rather than stand-alone diagnoses.

The most useful follow-up is not to chase every borderline parameter with supplements. Confirm a meaningful abnormality, examine the man, review varicocele/testicular size, hormones when indicated and the couple’s reproductive timeline, then decide whether natural attempts, treatment of a correctable male factor, IUI or IVF/ICSI is realistic.

What to bring for consultation

• All semen analyses with abstinence duration and collection notes.
• Hormone reports if already done.
• Scrotal ultrasound/Doppler if performed.
• List of medicines, supplements, testosterone or anabolic steroid use.
• Basic fertility evaluation of the female partner if available.

FAQs

Related reading

• FSH, LH and Prolactin in Men
• Testosterone Report Explained
• Scrotal Ultrasound Report Explained
• Kidney Stone Analysis Report Explained
• Urologist in Latur

References

• World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: WHO; 2021 https://www.who.int/publications/i/item/9789240030787
• American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline (2020; amended 2024) https://www.auanet.org/guidelines-and-quality/guidelines/male-infertility
• European Association of Urology. EAU Guidelines on Sexual and Reproductive Health: Male Infertility. 2026 https://uroweb.org/guidelines/sexual-and-reproductive-health/chapter/male-infertility