Male Fertility Test
Semen Analysis
A complete guide to the semen analysis test: what each parameter measures, how results are interpreted using WHO 2021 reference values, and what steps follow abnormal findings.
Test Overview
A semen analysis evaluates the physical properties of semen and the quantity, movement, and structure of sperm cells. It is the most informative first-line test for male reproductive function and can be completed without surgical intervention. Male factor infertility contributes to approximately 40 to 50% of all infertility cases, making this test a standard part of any fertility workup.
Key Timing
Sample collection requires 2 to 5 days of ejaculatory abstinence before the test. Fewer than 2 days may reduce sperm count and volume. More than 7 days is associated with lower motility and higher DNA fragmentation in the sample.
1. Purpose and uses of the semen analysis
- Screen for male factor infertility as part of a couples fertility evaluation.
- Diagnose specific sperm disorders: low count (oligospermia), absent sperm (azoospermia), poor motility (asthenospermia), abnormal morphology (teratospermia), or combinations of these.
- Confirm successful vasectomy by verifying the absence of sperm post-procedure.
- Assess the outcome of surgical interventions: vasectomy reversal, varicocele repair, or hormonal treatment for male hypogonadism.
- Monitor sperm quality changes over time, including after lifestyle changes, treatment, or chemotherapy.
2. Collection procedure and preparation
Sperm are collected by masturbation into a sterile, wide-mouthed container provided by the clinic. Collection is ideally done on site to minimize transit time and temperature change. Some clinics permit home collection if the sample reaches the laboratory within 30 to 60 minutes and is kept at body temperature during transport.
Preparation requirements
- Abstinence: 2 to 5 days from the last ejaculation.
- Alcohol and recreational drugs: avoid for at least 3 months before testing. Sperm take approximately 72 to 90 days to complete development (spermatogenesis), so recent exposures affect the current sample.
- Fever or illness: a fever in the 3 months before testing can temporarily suppress sperm production. Inform the clinic if this applies. A second test after recovery gives a more accurate baseline.
- Lubricants: standard commercial lubricants contain compounds that are toxic to sperm. Do not use lubricants unless the clinic provides a sperm-safe option.
- Medications: inform the clinic of all medications, including testosterone supplements, which can suppress sperm production entirely.
3. Parameters measured and what each means
A complete semen analysis reports on multiple parameters simultaneously. Understanding each one separately helps interpret a result that may show problems in one area but not others.
| Parameter | What it measures | Why it matters |
|---|---|---|
| Volume | Total ejaculate volume in mL | Low volume may indicate blocked ducts or retrograde ejaculation |
| pH | Acidity of the sample | Low pH combined with low volume suggests blocked seminal vesicles |
| Sperm concentration | Sperm cells per mL | Directly reflects sperm production |
| Total sperm count | Concentration multiplied by volume | Most clinically useful count metric for IUI or IVF selection |
| Total motility | Percentage showing any movement | Non-motile sperm cannot fertilize an egg |
| Progressive motility | Percentage moving forward in a line or large curve | Only progressive sperm can reach and penetrate an egg |
| Morphology (Kruger) | Percentage with normal head, midpiece, and tail structure | Abnormal shape affects the ability to bind and penetrate the egg |
| Vitality | Percentage of live sperm | Useful when motility is very low: distinguishes dead sperm from live but immotile |
| Leukocytes | White blood cell count in the sample | Elevated count suggests infection or inflammation in the reproductive tract |
4. WHO 2021 reference values (6th edition)
The World Health Organization's 2021 6th edition reference limits are the current global clinical standard. These values represent the 5th percentile of semen parameters in a reference population of fertile men. A result below these thresholds does not confirm infertility but indicates reduced reproductive potential.
| Parameter | WHO 2021 lower reference limit | Clinical implication if below |
|---|---|---|
| Volume | 1.4 mL | Hypospermia; investigate ducts and glands |
| Total sperm count | 39 million per ejaculate | Oligospermia by total count |
| Sperm concentration | 16 million per mL | Oligospermia by concentration |
| Total motility | 42% | Asthenospermia |
| Progressive motility | 30% | Reduced forward movement |
| Morphology (Kruger strict) | 4% normal forms | Teratospermia; ICSI more commonly recommended |
| Vitality | 54% live | Necrospermia if very low with normal count |
| pH | 7.2 or above | Low pH with low volume: obstruction suspected |
The 2021 edition lowered the concentration threshold from 15 to 16 million per mL and the total count threshold to 39 million. Reports referencing the 5th edition (2010) may show slightly different cutoffs.
5. Interpreting results: key terminology
Semen analysis reports use specific medical terms to describe patterns of abnormality. These appear on laboratory reports and are useful to recognize when reviewing results.
| Term | Definition | What it means in practice |
|---|---|---|
| Normozoospermia | All parameters within reference limits | Male factor is unlikely; female evaluation continues |
| Oligozoospermia | Concentration below 16 million/mL | IUI or IVF depending on severity |
| Severe oligozoospermia | Concentration below 5 million/mL | IVF with ICSI; hormonal workup required |
| Azoospermia | No sperm in the ejaculate | Differentiate obstructive from non-obstructive cause |
| Asthenozoospermia | Progressive motility below 30% | Reduces natural conception probability; ICSI often preferred |
| Teratozoospermia | Normal morphology below 4% | ICSI usually recommended over standard IVF insemination |
| OAT syndrome | Low count, motility, and morphology combined | Significant male factor; ICSI is standard |
| Leukocytospermia | WBC count above 1 million per mL | Infection or inflammation present; further investigation needed |
A single abnormal result should not be treated as a final diagnosis. Sperm quality fluctuates with health, temperature exposure, stress, and illness. A repeat test 4 to 12 weeks later is standard before drawing clinical conclusions.
6. Next steps based on results
Normal result
A normal semen analysis makes significant male factor infertility less likely. The fertility evaluation shifts to the female partner. Some men with borderline normal results may still benefit from sperm DNA fragmentation testing, particularly in cases of unexplained infertility or recurrent miscarriage.
Mild to moderate abnormalities
Lifestyle review is recommended: abstinence timing, heat exposure, weight, smoking, and alcohol. A repeat test is ordered. IUI may be an appropriate first treatment step depending on female factor findings.
Severe oligospermia
Hormone testing is ordered: FSH, LH, testosterone, prolactin. Genetic testing may follow if a hormonal cause is not identified. Karyotype and Y-chromosome microdeletion analysis are offered to men with sperm counts below 5 million per mL.
Azoospermia
Classified as either obstructive (normal sperm production but physical blockage) or non-obstructive (production failure). Hormone testing, scrotal ultrasound, and in some cases genetic testing guide the workup. Surgical sperm retrieval options including TESA, MESA, and TESE are available depending on the underlying cause.