Complete Guide to Semen Analysis

What is semen analysis?

A diagnostic semen analysis examines a sample produced for fertility assessment. The laboratory records measurements and observations using defined methods. The WHO sixth-edition manual, published in 2021, provides the international framework for laboratory examination and processing.

Your report is a description of that sample under those collection and testing conditions. It is one piece of evidence in a wider assessment, alongside your medical history, symptoms and family-building circumstances.

A post-vasectomy semen check has a different purpose: assessing whether sperm remain after a vasectomy. Do not assume a service offering that check is also providing a full diagnostic fertility analysis. Confirm which test has been ordered.

Before you book a sperm test

Start with your reason for testing: curiosity, preconception planning, sperm freezing, an existing concern or a treatment decision. You can seek testing or advice at any of these stages. Deciding what you want to know helps you choose a useful assessment and an explanation that fits your plans.

Ask what the test includes. A limited screening product may answer a narrower question than a full laboratory semen analysis. Check whether the service measures count, movement and shape, where analysis happens and who explains the report.

Confirm whether you need an appointment, a specific container or a referral, and whether you will produce the sample on site or at home. Arrange the journey around the laboratory's delivery deadline rather than assuming you can post or drop off a fresh sample at any time.

Plan the results conversation as well as the sample appointment. Ask how you will receive the report, what happens if a finding needs follow-up and whether interpretation is included in the price. Keep the complete report for any later specialist review.

Sample collection: preparing correctly

Follow the abstinence interval in your own test instructions. Collection protocols can differ between services, so do not substitute a generic online recommendation for the guidance supplied with your ProFertility test. A longer interval does not automatically make the result more useful.

Use the laboratory-approved container. Collect the whole ejaculate, and tell staff if any part was missed. Avoid ordinary condoms, oils or lubricants unless the laboratory specifically supplies or approves an alternative. If producing a sample is difficult, ask the service for help before the appointment.

Record the production time and complete the requested identification and questionnaire. Delivery time and temperature matter, but the exact requirements are service-specific. Ask what to do if travel is delayed rather than applying another hospital's instructions to your sample.

Tell the clinician about recent illness and relevant medicines or substances. Do not stop prescribed medication for the test without advice. Collection details should travel with the report so the result can be interpreted fairly.

WHO reference values: what the numbers mean

The table below shows commonly used WHO 2021 lower reference values, checked against published andrology reference tables. These are fifth-centile values with an associated confidence interval. We show the central values here, not the confidence intervals.

These values come from the distribution of measurements in men whose partners became pregnant within 12 months. They are not a target to maximise or a binary fertility test. Someone below a value may still conceive, and someone above it is not guaranteed a pregnancy.

Use the values and comments on your actual laboratory report when discussing your result. Units, methods and any laboratory-specific interpretation need to be understood. A small numerical difference around a reference value should not be turned into a dramatic conclusion without context.

Semen volume

Volume is the amount of fluid in the sample, measured in millilitres. It is not the same as sperm count. Most of the ejaculate is fluid carrying sperm rather than sperm themselves.

Start by checking whether the whole sample was collected. A low-volume finding should be considered with collection details and the rest of the report, rather than used alone to identify a cause.

Do not try to infer volume from how the ejaculate looks or from a comparison with an earlier occasion. The laboratory measurement and any repeat assessment are more useful.

Sperm concentration and total sperm number

Concentration is the number of sperm per millilitre. Total sperm number describes the number in the whole ejaculate. Volume therefore affects total number even when concentration is unchanged.

For a simplified example, a 2 mL sample with a concentration of 20 million per mL contains 40 million sperm in total. A 1 mL sample at the same concentration contains 20 million. These are arithmetic examples, not predictions of fertility or treatment recommendations.

Read the units carefully. Reports may write 16 million per mL as 16 × 10⁶/mL. Do not compare a concentration result with the reference for total number, or confuse either with the number of moving sperm.

If you are comparing reports, note changes in volume as well as concentration. Ask which measurement is relevant to the decision being discussed rather than assuming the largest-looking number is the important one.

Motility: how sperm move

Motility describes movement. Progressive sperm move forward; non-progressive sperm move without effective forward progression; immotile sperm do not move in the assessment. Total motility includes progressive and non-progressive movement.

That is why total motility and progressive motility have different reference values. Check the label before comparing percentages across reports. Some laboratories may use additional subcategories; ask for the definitions used.

A high concentration does not cancel out a movement finding, and a lower movement percentage should not be read without the rest of the sample. Ask the clinician to explain the combined pattern and whether sample handling affects confidence in the result.

Morphology: sperm shape

Morphology is the percentage of sperm meeting the laboratory's criteria for normal shape. Strict criteria mean the percentage can look surprisingly low even in a sample within reference values. The commonly used lower reference value is 4%.

A morphology result is not a statement that the remaining sperm are incapable of contributing to pregnancy. Nor is it a percentage chance of having a healthy baby. It is a laboratory description with a specific method.

Ask whether morphology is an isolated finding or part of a broader pattern. Avoid making a treatment decision from this line alone, especially when you have not yet had the report explained.

Vitality: are sperm alive?

Vitality assesses whether sperm are alive. It is different from motility: a sperm can be alive without moving. This distinction can matter when interpreting a sample with little movement.

Not every report includes every parameter. If vitality is absent, ask whether it was indicated and measured rather than assuming it was normal or abnormal. The scope of the test should be clear.

Read any laboratory comment alongside the percentage. A result needs interpretation in the context of the sample and other measurements, not as a separate score to optimise.

Other observations on the report

Depending on the service and findings, a report may include pH, appearance, liquefaction, viscosity, cells or other observations. These are not all interchangeable diagnostic tests.

Ask which comments are clinically relevant and which simply describe the sample. Do not assume a note proves infection or explains why conception has not happened. A clinician may need history, examination or a different investigation to answer that question.

A report marked unsuitable, incomplete or limited requires a different conversation from a reliable report with an abnormal measurement. First establish whether the sample can answer the intended question.

What do abnormal results mean?

An abnormal report identifies one or more findings outside the expected values. It does not automatically establish the cause or mean that pregnancy is impossible. The next decision depends on the severity, reliability and wider context.

You may see terms such as oligozoospermia for reduced sperm concentration, asthenozoospermia for reduced motility, teratozoospermia for reduced normal morphology or azoospermia when no sperm are found. Ask for a plain-language explanation rather than treating the term as a final prognosis.

If no sperm are reported or findings are markedly abnormal, arrange a clinical discussion promptly. Ask what needs confirmation and whether specialist investigation should happen now. Do not spend months trying to correct a severe finding with unreviewed supplements.

Keep a written next-step plan. It should distinguish repeating a questionable sample, confirming a persistent finding and investigating a potential medical cause.

When should semen analysis be repeated?

A repeat can clarify whether a finding persists or help assess a new sperm-production cycle. An interval of around three months may be appropriate for that purpose. Severe findings or collection problems can justify earlier action. The timing should answer a specific clinical question; it is not an instruction to wait before your first test.

Tell the clinician if the sample was incomplete or collection and delivery instructions were not met. A repeat arranged to address a collection problem may have a different rationale from one intended to assess a change over time.

Compare like with like where possible: retain the reports, note abstinence intervals and sample circumstances, and check whether the same measurements were reported. A change in one number is not automatically an improvement in the whole fertility picture.

Ask what either repeat outcome would mean. If it is reassuring, does another decision remain? If the finding persists, who arranges the further assessment? A repeat test should move the plan forward.

Normal results but still not pregnant

If you are still struggling to conceive despite a reassuring semen analysis, review what has been assessed across both partners and how long you have been trying. A normal result does not test every step needed for conception.

This is a specific situation, not a reason for people with normal results to become alarmed. The right question is whether further assessment is justified by your circumstances, rather than whether every reassuring test hides a problem.

Our separate guide on normal semen analysis but not pregnant explores that review. It connects the sperm report with the wider pathway instead of treating an extra male test as the inevitable answer.

Semen analysis and DNA fragmentation

A routine semen analysis does not measure sperm DNA fragmentation. Fragmentation tests use different methods to examine DNA damage; the HFEA notes that methods and thresholds are not standardised and that the result is unlikely to change treatment management.

Current NICE NG257 advises against testing sperm DNA integrity in the fertility pathway. An additional test should therefore not be promoted as a routine upgrade or as necessary reassurance after a normal semen report.

If a clinic suggests it, ask why it is being offered, how the recommendation relates to current guidance and what would change after either result. Discuss the evidence for any proposed intervention as well as the test itself.

Recommended next steps

If you are curious or planning ahead, use the test to start an informed conversation about sperm health and the limits of what a sample can tell you. If you are trying now, connect the report with practical TTC support and the wider fertility picture. Men and partners should be included early.

If you have confusing or concerning results, a standalone consultation or second opinion can review the full report and identify what remains unanswered. Where relevant, the next step may be confirmation, targeted investigation, action on a modifiable factor or specialist referral.

For structured follow-through, the six-month ProFertility Plan connects possible barrier identification, targeted investigations, clinical review and a personalised improvement programme. It can also support appropriate work alongside IVF or other treatment, with decisions coordinated with your treating clinicians.

Some findings need prompt medical care; a programme should not delay it. The aim is to give you a clearer route and more informed choices, without promising that testing or optimisation will remove every barrier or replace necessary treatment.

You can also begin with free Frank or HerStory registration and learn at your own pace. Education is a worthwhile next step in its own right, including when parenthood is not your immediate goal.

Related guidance and support

• Complete Guide to Male Fertility
• Normal semen analysis but not pregnant: what next?
• Which fertility tests should a couple consider?
• How long should you try before fertility testing?
• Testing when you are single
• Explore the six-month ProFertility Plan
• Frank: free male fertility education and community
• HerStory: female fertility education and community
• TTC Toolkit: practical support while trying

Related blog articles

• What a personalised fertility care plan should do

Frequently asked questions