Low sperm motility means fewer sperm than expected are moving, especially moving forward effectively. WHO 2021 gives lower reference values of about 42% total motility and 30% progressive motility. A low result does not automatically mean pregnancy is impossible. It may be temporary after fever or poor sample handling, or associated with varicocele, prolonged abstinence, inflammation, oxidative stress, primary sperm dysfunction or other male infertility causes. The report should be interpreted with sperm count, morphology, vitality and the couple’s fertility history.

What does low sperm motility mean?

Low motility is called asthenozoospermia or asthenospermia. Laboratories may report progressive, non-progressive and immotile sperm. Progressive motility matters because sperm that only vibrate or move in small circles are less useful for travelling through the female reproductive tract. When almost all sperm are immotile, vitality testing helps distinguish live but non-moving sperm from dead sperm.

Common causes of low sperm motility

• Recent fever or systemic illness.
• Delay or temperature problems between sample collection and laboratory assessment.
• Prolonged abstinence in some men.
• Clinical varicocele.
• Smoking, obesity and other oxidative-stress exposures.
• Genital tract inflammation or infection in selected men.
• Primary structural or functional sperm disorders; rare severe cases can be genetic.
• Low sperm vitality or necrozoospermia.
• A combined semen problem such as oligoasthenoteratospermia.

How the result is confirmed

Review collection details first. Motility is one of the parameters most sensitive to transport time and temperature. If the result is abnormal, repeat testing after an appropriate interval is often needed. The report should include vitality when motility is very low. Men with persistent severe asthenozoospermia need examination and targeted tests rather than repeated empirical supplements.

Does this result mean infertility?

No single semen parameter by itself can reliably label a man fertile or infertile. The chance of pregnancy depends on the severity and persistence of the abnormality, other semen parameters, sexual timing and the female partner’s fertility. A pattern involving several abnormal parameters is usually more clinically important than one mildly abnormal value.

Treatment depends on the cause

Treatment targets the cause: correct fever-related timing, stop fertility-suppressing hormones, treat proven genital infection, consider varicocele repair when the usual infertility indications are met, and address smoking, obesity or heat exposure. When motility remains poor, assisted reproduction may bypass part of the motility problem; ICSI can fertilise an oocyte using a single selected sperm, although the decision depends on the couple’s complete evaluation.

What not to do

• Do not assume a single low-motility sample reflects a permanent sperm defect.
• Do not confuse total motility with progressive motility.
• Do not use antibiotics merely because motility is low.
• Do not assume antioxidant supplements can replace evaluation of a severe abnormality.
• Do not ignore near-zero motility; vitality testing and specialist review are important.

When low sperm motility deserves specialist review

• Progressive motility is very low or remains abnormal despite a properly collected repeat sample.
• Nearly all sperm are immotile, because vitality testing may be needed to determine whether the sperm are alive.
• Low motility occurs together with a low sperm count, poor morphology, a palpable varicocele or another testicular abnormality.
• There is a history of high fever, genital infection, testicular disease, chemotherapy, or use of testosterone/anabolic steroids.
• The couple is deciding between continued natural attempts, IUI and IVF/ICSI, or has had previous fertilisation-treatment difficulty.

When low motility may be a testing issue

Motility is especially sensitive to how the sample is collected and handled. A long delay before analysis, exposure to unsuitable temperatures, incomplete collection or a markedly different abstinence interval can alter the result. If the abnormality is mild and the rest of the semen profile is reassuring, repeating the test under standardized conditions may be more useful than starting treatment from one number.

When nearly all sperm are immotile, vitality testing becomes important. It separates live sperm that are not moving from sperm that are dead, which changes both diagnosis and the way an IVF laboratory may handle the sample. Severe isolated motility loss is therefore interpreted differently from low motility occurring together with low count and poor morphology.

What to bring for consultation

Bring these if available:

• Semen reports showing progressive motility, total motility and vitality if it was measured.
• The abstinence interval, collection method and approximate time from collection to laboratory analysis.
• Details of recent fever, infection or major illness that could temporarily reduce motility.
• Scrotal Doppler, hormone reports and a list of medicines, testosterone or anabolic steroids if relevant.
• Previous fertility-treatment records and the partner’s fertility evaluation if available.

FAQs

Related reading

• Semen Analysis Report Explained
• Asthenospermia Explained
• Oligoasthenoteratospermia Explained
• Varicocele and Male Infertility
• Fever and Sperm Count: When to Repeat Test
• Urologist in Latur

References

• World Health Organization. WHO laboratory manual for the examination and processing of human semen, 6th ed https://www.who.int/publications/i/item/9789240030787
• World Health Organization. Guideline for the prevention, diagnosis and treatment of infertility. 2025 https://www.who.int/publications/i/item/9789240115774
• 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
• 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/documents/Guidelines/PDF/2024%20Guidelines/Male%20Infertility%20Unabridged%20Final.pdf