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Health condition

Poor sperm motility

Poor sperm motility (asthenozoospermia) means too few sperm swim effectively - a common, often improvable finding on semen analysis.

Last reviewed 2026-09-27 · Next review due 2027-09-27

Key points

  • Motility is graded on semen analysis as progressive, non-progressive or immotile

  • Causes include varicocele, infection, antisperm antibodies, heat, smoking and prolonged abstinence

  • An abnormal result should be repeated before drawing conclusions

  • A urologist/andrologist can investigate and treat underlying causes

  • ICSI overcomes even severe motility problems in assisted conception

Understanding it

About Poor sperm motility.

Sperm must swim through cervical mucus, the uterus and the fallopian tube to reach the egg, so motility matters as much as count. Low motility often accompanies other semen abnormalities and shares many of the same reversible causes.

Repeat analysis with attention to collection technique, screening for infection and varicocele, and lifestyle optimisation; assisted conception techniques are highly effective when motility remains poor. On the NHS, routine referrals of this kind often take 20-45+ weeks in many areas, whereas a private fertility specialist can typically see you within around two weeks, with any tests and treatment arranged promptly afterwards.

A quiet reminder

This guide is for information, not medical advice.

Your GP or specialist knows your history and can tell you which parts apply to you. If in doubt, see them - and treat sudden severe symptoms as an emergency.

Frequently asked

Common questions about Poor sperm motility.

Quick, plain-English answers to what people ask us most.

  • What is poor sperm motility?

    Poor sperm motility, also called asthenozoospermia, means a lower-than-normal proportion of sperm are able to move properly, which can reduce the chances of natural conception.

  • What causes poor sperm motility?

    Causes include infections, varicocele (enlarged veins in the scrotum), hormonal imbalances, smoking, excessive alcohol use, certain medications, heat exposure, and sometimes no clear cause is identified.

  • What are the symptoms of poor sperm motility?

    There are usually no noticeable symptoms directly related to sperm motility itself; it's typically identified through a semen analysis performed as part of a fertility investigation.

  • Is poor sperm motility a serious problem?

    It's not dangerous to health, but it can significantly affect fertility, and depending on severity, natural conception may take longer or require assisted reproduction techniques.

  • Can poor sperm motility be treated?

    Treatment depends on the underlying cause; lifestyle changes (reducing alcohol, stopping smoking, avoiding excessive heat), treating any identified infection or hormonal imbalance, and, for persistent cases, assisted reproduction techniques can help.

  • How is poor sperm motility diagnosed?

    A semen analysis is the key test, assessing sperm count, motility, and shape, sometimes repeated to confirm findings, alongside further tests to look for an underlying cause if needed.

  • How long does it take to see improvement with lifestyle changes?

    Since sperm take around three months to fully develop, lifestyle changes such as stopping smoking or reducing alcohol typically need to be sustained for at least this long before assessing their effect on semen analysis results.

  • Poor sperm motility vs low sperm count — what's the difference?

    Low sperm count refers to fewer sperm overall, while poor motility means a lower proportion of those sperm can move effectively; these can occur separately or together, and both are assessed together on a standard semen analysis.

  • Can poor sperm motility improve on its own?

    It can fluctuate over time, particularly if related to a temporary factor such as illness or heat exposure, but persistent or significant abnormalities usually benefit from specific assessment and, if a cause is found, targeted treatment.

  • When should I see a specialist, and how quickly can I be seen privately?

    See a fertility specialist or urologist if a semen analysis shows reduced motility, particularly if trying to conceive. Private fertility assessment is typically available within about two weeks, considerably faster than standard NHS fertility referral pathways.