Sperm Motility: What It Is, Normal Levels, and How It Affects Fertility

• What is sperm motility?
• What is considered normal sperm motility?
• How sperm motility affects fertility
• Sperm motility vs sperm count and morphology
• How is sperm motility tested?
• What causes low sperm motility?
• How to improve sperm motility
• Treatment options if sperm motility is low

Sperm motility refers to how efficiently sperm move through the female reproductive tract and toward the egg. As sperm must swim from the vaginal canal through the cervix and into the uterus to fertilise the egg, good sperm motility is necessary to conceive via sexual intercourse. Sperm cells must swim quickly and directly if they are to successfully reach the egg. The more efficient, motile sperm in your semen, the better the chances of conception. 

Types of sperm motility

Experts refer to several types of sperm motility as not all sperm cells move in the same way. There are four main motility terms:

• Progressive motility – sperm cells that predominantly move in straight lines and at a minimum of 25 micrometres per second are progressively motile. This is a key indicator of healthy sperm.
• Non-progressive motility – sperm cells that are moving but not progressing forward are non-progressively motile. They may not be progressing because they are moving in tight circles or are at less than 5 micrometres a second.
• Immotile sperm – sperm cells that show no sign of movement at all are immotile.
• Total motility – refers to the total number of moving sperm cells in a semen sample, including both progressive and non-progressive sperm.

“Normal” or healthy sperm motility is when more than 32% of sperm in ejaculate have progressive motility and total motility is more than 40%, according to the World Health Organization (WHO). 

It is also perfectly normal for your semen to contain some immotile sperm. Even in semen samples showing healthy levels of sperm motility, up to 60% of the sperm cells could be immotile. 

However, healthy sperm motility is no guarantee of fertility, as other factors can prevent conception. For instance, sperm concentration (the number of sperm cells per millilitre of semen) and sperm morphology (the shape of sperm cells) also impact male fertility. Likewise, erectile dysfunction or damaged sperm cells may prevent you from conceiving.

When is sperm considered “abnormal”?

Normospermia is the medical term for sperm that meets all the WHO’s parameters for healthy motility, concentration, morphology and semen volume. 

There are several motility-related medical terms that describe conditions where sperm do not meet these criteria. They include:

• Asthenozoospermia – the medical term for reduced or low sperm motility. The WHO defines asthenozoospermia as occurring when less than 32% of sperm cells in ejaculate have progressive motility or when total motility is less than 40%. It is one of the leading causes of male infertility.
• Azoospermia – a medical condition in which a man’s semen contains no sperm. Approximately 1% of all men suffer from azoospermia.
• Hyperspermia – a medical condition where a man ejaculates an abnormally large amount of semen, usually over 5.5 ml. This can affect sperm concentration and motility, and contribute to fertility challenges.

Sperm motility affects fertility and the likelihood of conception because sperm must move far enough, and in the right direction, to reach an egg. Sperm with low motility that cannot move quickly and efficiently are less likely to be able to swim the necessary distance and reach the egg. Sperm motility is a key indicator of sperm quality, and low sperm motility is one of the main causes of male infertility.

What sperm motility results mean for pregnancy

Low sperm motility occurs at different levels of severity, and just because you suffer from asthenozoospermia does not mean you cannot conceive. In some instances, it may just take longer to do so. 

However, the more severe the motility issues, the less likely the chances of getting pregnant via unprotected sexual intercourse, and the more likely you will require fertility treatment to conceive.

(Source: NHS)

Sperm motility, sperm count and sperm morphology are three of the most important indicators of sperm quality.

Sperm count

Sperm count is the number of sperm per millilitre (mL). Sometimes referred to as sperm concentration. Anything over 15 million sperm per mL is considered a healthy concentration. A count below 15 million per mL is regarded as a low sperm count and known medically as oligozoospermia.

Sperm morphology

Sperm morphology is the size and shape of sperm. Healthy sperm resemble tadpoles and have a smooth, oval head with a clear nucleus, a straight midpiece and a long, uncoiled tail. Abnormal sperm may have a misshapen or doubled head, lumps, or a coiled or split tail. 

Sperm morphology can also refer to the percentage of sperm with a healthy shape in a semen sample. All semen samples contain a significant number of abnormally shaped sperm. In semen with normal sperm morphology, at least 4% of sperm cells will meet the definition of healthy morphology (WHO). Teratozoospermia is the term for the medical condition where less than 4% of sperm cells have a healthy morphology.

Impact of morphology and concentration on fertility

Both oligozoospermia (low sperm count) and teratozoospermia (abnormal sperm morphology) impact the chances of conception and make pregnancy via sexual intercourse less likely. While men with oligozoospermia and teratozoospermia may still conceive, it can take longer. Severe cases may require fertility treatment.

Male fertility challenges can be caused by poor sperm motility, count or morphology, or a combination of these three factors. Certain lifestyle choices, such as smoking, negatively impact motility, morphology and count.      

Sperm motility is tested as part of wider semen analysis. Fertility clinics can conduct semen analysis if you are concerned about your fertility, and the test is used by licensed sperm banks to guarantee the quality of donations.  

Sperm motility is expressed as a percentage figure. This is the percentage of sperm that are moving forward at a minimum of 25 micrometres per second (progressive motility). As part of the semen analysis, you may also receive a figure for total motility, the percentage of progressively and non-progressively motile sperm in the sample. 

Semen analysis involves:

1. Provide a semen sample – this usually takes place at a clinic, as sperm motility is best analysed within an hour of the sample being taken.
2. Lab analysis – the lab will analyse the sperm underneath the microscope and evaluate several hundred cells to measure motility. Computer software can be used to generate a more accurate result.
3. Results – lab technicians will calculate the percentage of sperm that are progressively and non-progressively motile, and present the sperm analysis results.

You can attempt to begin increasing sperm motility by making lifestyle changes, such as stopping smoking, reducing your alcohol intake or adopting a healthier diet. While these changes may help some men conceive, fertility is complex, and there are often several contributing causes for fertility challenges.

Lifestyle changes that may help improve sperm motility

The following lifestyle changes may help improve sperm motility. As it takes approximately 75 days to produce and mature a sperm cell, these changes will need to be maintained for two to three months before any potential benefits come to fruition.

• Quit smoking – experts recommend stopping smoking entirely when trying to conceive.
• Reduce alcohol consumption – men trying to conceive should reduce alcohol consumption significantly. Complete cessation is preferable.
• Exercise regularly – exercise promotes healthy hormone production and helps manage body weight.
• Eat a healthier diet – encourages better weight management and provides you with nutrients that may assist with healthy sperm production.
• Avoid environmental hazards – gives sperm cells the best chance of developing healthily.
• Limit exposure to stress – restores hormonal balance, promotes healthy sperm production and could improve motility.

Supplements and medical support

Some scientific studies seem to link certain supplements and vitamins with improved sperm motility. These include:

• Coenzyme Q10 (CoQ10)
• Zinc and selenium
• Folic Acid
• Omega-3 

However, there is very limited evidence to support these claims, and the value of supplements for improving sperm motility is disputed in the scientific community. If you are experiencing fertility challenges and considering supplements, we recommend fertility support from a healthcare professional. They’ll be able to give you an evidence-based argument for why you should or shouldn’t use fertility supplements.

If lifestyle changes don’t have the desired effect and your sperm motility remains low, there are still plenty of options available to you. You can pursue fertility treatments that bypass sperm motility issues by isolating healthy sperm, consider using a sperm donor, or think about fostering or adopting.

When to consider fertility support

Generally, you should seek help and fertility support from healthcare professionals if you have been having regular unprotected sex for over 12 months without conceiving. If you or your partner is over the age of 35, you should seek support after six months. 

Of course, there are no hard and fast rules, and you can and should always seek support if you’re worried about your fertility or think something isn’t right. Today, fertility treatments and assisted reproductive technology (ART) are highly advanced, and there’s a lot fertility specialists can do to help you become a parent. The sooner you’re aware of any issues, the sooner you and your fertility specialists can begin working together to overcome them.

Using donor sperm to conceive

For some men, sperm motility will be an insurmountable problem, and that might mean looking at other ways to become a father. One of the most common is using donor sperm sourced from a licensed sperm bank to conceive with a fertility treatment like ICI, IUI or IVF. 

Sperm donors donating to licensed sperm banks are screened for contagious diseases and transmittable infections. They are also screened to ensure high sperm quality and healthy motility. 

While using a sperm donor can feel like a big step, there are plenty of resources available to help you learn more about donor conception and work out whether it’s the right option for you. Our guide for couples considering using donor sperm is a great place to start.

What is a good sperm motility percentage?

Healthy sperm motility is when over 32% of sperm are progressively motile and total motility is 40% or above.

Can you get pregnant with low sperm motility?

Yes, you can get pregnant with low sperm motility. Low sperm motility is a sliding scale. If 30% of your sperm are progressively motile, there’s still a good chance you could conceive through sexual intercourse. However, if only 5% are progressively motile, your chances are drastically reduced. 

In all cases, fertility treatments may be able to help you conceive using your own sperm, even if low motility is a concern.

Can sperm motility improve over time?

Yes, sperm motility can improve over time if you make lifestyle changes. These changes need to be made and sustained for two to three months before potential benefits are realised, as this is how long it takes to produce and mature a sperm cell.

What does immotile sperm mean?

Immotile sperm shows no sign of movement and cannot move towards the egg to fertilise it. All semen, even semen considered to have good motility levels, will contain a significant percentage of immotile sperm.