A semen analysis (sometimes called a sperm test or seminogram) is the starting point for checking male fertility. You produce a sample by masturbation into a sterile pot, either at the clinic or at home with strict instructions on getting it to the lab quickly and kept at body temperature.
The lab then measures the volume of the sample, how many sperm it contains (concentration and total count), how many are moving (motility) and how many are normally shaped (morphology). Many labs also report things like pH, vitality (the share of live sperm) and white blood cells.
Results are compared with reference values published by the World Health Organization (WHO). The current figures, from its 2021 manual, are based on more than 3,500 men from twelve countries whose partners had recently conceived.1 Each limit marks the 5th centile of that group, not the average.
What does a semen analysis measure?
The core measures are volume, sperm concentration, total sperm count, motility and morphology. Each has a WHO lower reference limit, and each is read in the context of the others.
The WHO 2021 lower reference limits are shown below.1 Each has its own glossary entry if you want the detail.
- Semen volume: 1.4 mL
- Sperm concentration: 16 million per mL
- Total sperm count: 39 million per ejaculate
- Motility: 42% total, 30% progressive
- Morphology: 4% normal forms
How should I prepare for a semen analysis?
Follow the lab's instructions on abstinence, collection and delivery to the letter. Avoid going much longer without ejaculating than the lab asks, because very long gaps can make results worse, not better.
Labs set an abstinence window so results are comparable. An analysis of 9,489 samples found that in men with normal concentrations, motility and the proportion of normally shaped sperm were significantly lower after 11 to 14 days of abstinence; the authors advised not exceeding 10 days.3 See ejaculatory abstinence for more.
Collect the whole ejaculate in the pot provided, and tell the lab if any was lost. Use only the pot the lab gives you, follow its rules on lubricants and condoms, and mention any recent fever, illness or new medicines.
What do semen analysis results mean?
Results below a reference limit flag something to look into; they are not a diagnosis. A single sample is a snapshot, so an abnormal result is normally repeated.
The researchers behind the 2021 values point out that the reference limits do not mark a clear line between fertile and subfertile men.1 Plenty of men below one limit conceive naturally.
Results also swing from sample to sample. In a study of men who each gave five or more samples, sperm count varied by around 46% to 54% within the same man, and the author concluded that at least three samples were needed for a reliable picture.2 One study is not the last word on how many tests you need, but it explains why doctors are wary of a single result.
When should a man get a semen analysis?
When a couple is having trouble conceiving, the man should be tested alongside his partner, not after her. It is a simple, non-invasive test that often guides what happens next.
European Association of Urology guidance notes that roughly half of infertility involves problems with the male partner, and recommends that infertile men have a full urological assessment.4 It also notes that men with infertility have a higher risk of other conditions, including cardiovascular disease and some cancers, so the assessment matters for general health too.4
Ask your GP about a semen analysis if you and your partner have been trying without success, or sooner if you have a history of testicular problems, surgery or cancer treatment. See a doctor promptly for any lump, pain or swelling in the testes. Our guide to lifestyle factors that affect male fertility covers what you can do in the meantime.
Common questions
How long should I abstain before a semen analysis?
Follow your lab's instructions, as they set a specific window so results can be compared. Research suggests going much longer than asked is counterproductive, with motility and morphology lower after 11 to 14 days.3
Are home sperm tests as good as a lab semen analysis?
No. Home kits can be a rough first screen, but a lab analysis assesses several parameters together, under controlled conditions, and is what a doctor will need to make decisions.
Is one normal semen analysis enough?
A normal result is reassuring, though it does not guarantee fertility. An abnormal result should be repeated, because semen results vary a lot from one sample to the next.2
Read more on this
Lifestyle factors that affect male fertility: a practical guide
Is it normal for semen volume to change day to day?
How long does it take sperm to regenerate?
Sources
- Campbell MJ, Lotti F, Baldi E, et al. Distribution of semen examination results 2020 - A follow up of data collated for the WHO semen analysis manual 2010. Andrology. 2021;9(3):817-822. PubMed
- Keel BA. Within- and between-subject variation in semen parameters in infertile men and normal semen donors. Fertil Steril. 2006;85(1):128-134. PubMed
- Levitas E, Lunenfeld E, Weiss N, et al. Relationship between the duration of sexual abstinence and semen quality: analysis of 9,489 semen samples. Fertil Steril. 2005;83(6):1680-1686. PubMed
- Minhas S, Bettocchi C, Boeri L, et al. European Association of Urology guidelines on male sexual and reproductive health: 2021 update on male infertility. Eur Urol. 2021;80(5):603-620. PubMed
Not medical advice. Written by Eric Stephens from the research cited above; not reviewed by a doctor. If something worries you, see a GP.