The short version
Sperm motility is the percentage of your sperm that are moving, and how well they move. The WHO reference is at least about 40% total motility, with a good share of those moving forward. A sperm that cannot swim cannot reach an egg, which is why movement can matter as much as count.
- Progressive motility (moving forward) matters more than sperm that only twitch in place.
- The key combined figure is total motile count: how many moving sperm are in the whole sample.
- Low motility is called asthenozoospermia. It has many treatable causes.
- Heat, lifestyle, and time between collection and analysis all affect the reading.
Count gets the attention, but movement is what does the work. A sperm has to travel a long way to reach an egg, and a high count of sperm that cannot swim well is less useful than a moderate count that can. Motility is the measurement that captures this, and it is often where a fertility problem actually shows up.
What motility measures
Motility is the percentage of sperm in your sample that are moving. A lab does not just count movers and non-movers, though. It grades the quality of the movement, which is the part that matters:
- Progressive motility means the sperm are swimming forward, in roughly a straight line or large circles. This is the movement that gets a sperm where it needs to go.
- Non-progressive motility means the sperm are moving but not advancing, twitching or swimming in tight circles.
- Immotile sperm are not moving at all.
When you read a report, the progressive number is the one to focus on. Total motility lumps progressive and non-progressive together, but only progressive movement is truly useful for conception. For how this fits with the other measures, see the male fertility testing guide.
The reference values
The World Health Organization reference values put the lower limit at:
- Total motility: at least about 40% of sperm moving.
- Progressive motility: at least about 30% moving forward.
As with count, these are lower reference limits drawn from men who conceived within a year, not a hard fertility cutoff. Being a little under does not mean conception is off the table, and being over is not a guarantee.
Total motile count: the number that ties it together
If you remember one figure from a semen analysis, make it total motile count. It is volume times concentration times the percentage of progressively motile sperm, which means it answers the practical question: how many genuinely useful sperm are in this sample?
This is why motility and count cannot be read in isolation. A strong count with weak motility and a weaker count with strong motility can land at the same total motile count. Specialists lean on this number because it reflects the real working population of sperm. The count side of the equation is in sperm count explained.
What low motility means
Low motility is called asthenozoospermia. Common contributors include:
- Heat exposure, which sperm are especially sensitive to. Frequent hot tubs, saunas, or a laptop on the lap can lower motility.
- Lifestyle factors, including smoking, heavy alcohol use, and excess weight.
- Varicocele, which can raise scrotal temperature and impair movement.
- Oxidative stress, where an imbalance damages sperm cells.
- A long gap since last ejaculation, which lets older, less motile sperm accumulate.
Many of these are addressable. What helps, and what is just noise, is covered in how to improve your sperm count, which applies to motility as well.
A collection caveat worth knowing
Motility is the parameter most sensitive to how a sample is handled. Sperm slow down and stop as they cool and as time passes outside the body, so a clinic sample that sits too long, or gets too cold or too hot in transit, can read as low motility that is really a handling artifact. An at-home mail-in kit addresses this with a preservative that stabilizes the sample for shipping, so the motility reading reflects your biology rather than the trip.
Measure motility at home
The Jack At-Home RSA Semen Analysis reports motility and total motile count alongside count and morphology, read by a CLIA-certified, CAP-accredited lab. Collect at home, mail it in, results in 1 to 2 days. $249.
Order the RSA test →FAQ
What is a normal sperm motility? The WHO reference is at least about 40% total motility and at least about 30% progressive motility. These are lower reference limits, not a strict cutoff.
What is the difference between progressive and non-progressive motility? Progressive means moving forward, which is what reaches an egg. Non-progressive means moving without advancing. Progressive motility is the more meaningful number.
What is total motile count? The number of moving sperm in the whole sample, combining volume, concentration, and motility. It is often the single most useful figure on a semen analysis.
Can low motility be improved? Often. Reducing heat exposure, addressing lifestyle factors, and treating a varicocele can help. Repeat testing shows whether changes are working.
Why did my motility read low when my count was fine? It can be biology, or it can be a handling artifact, since motility drops as a sample cools or sits. A preserved mail-in sample or a repeat test helps tell the difference.
Sources
- World Health Organization. Semen analysis reference values for motility.
- American Society for Reproductive Medicine. Interpreting motility and total motile count.
- Mayo Clinic: Male Infertility. Causes and evaluation of low motility.
Undeez is not a medical provider. Discuss your results with a physician who can interpret them in your context.
