Low sperm motility causes infertility due to an inability of sperm to travel to the egg. Learn more about what causes the condition, tips for improving, and how couples can potentially overcome this condition.
In biology, the term ‘motility’ describes an organism’s capability to move actively and on instinct . Sperm motility, then, refers to the ability of sperm cells to move efficiently – specifically, to be able to ‘swim’ through the birth canal and up to an ovulated egg.
Accordingly, low sperm motility — or sperm that is unable to move properly, also known as asthenozoospermia — can significantly reduce the chances of pregnancy . It is estimated that around 7% of men worldwide are affected by abnormalities in sperm motility, morphology and concentration, with ‘male factor’ infertility being the cause of 40% to 50% of all infertility cases .
In this article, we’ll be taking a closer look at low sperm motility, what affects the sperm’s ability to fertilise an egg and tips for couples facing low sperm motility to increase their chances of getting pregnant.
Why is sperm motility important?
Sperm motility is important because the sperm has to travel a long way to fertilise the egg . Let’s consider the route.
Upon ejaculation, sperm is deposited in the vagina, near the cervix. From there, some sperm find their way into the cervix and move into the uterus. They then continue moving onward towards the fallopian tubes, where the egg may be found.
The thing is, there are two tubes in the womb, and the egg may be released either in the left or right tube at any one time. Hence, sperm have a 50/50 chance of entering a tube that contains the egg. The entrance to the fallopian tubes are also narrow, making things trickier, although at this stage of the journey, chemical signals released by the egg should help them find the right way.
But arriving at the egg isn’t the end of the journey. Sperm must continue moving in order to penetrate the egg (which has a shell, called the zona pellucida) and go all the way through into the egg for fertilisation to take place .
What counts as low sperm motility?
There are 2 main factors to look at when determining the level of sperm motility, and that is speed and movement pattern.
Sperm must be able to move at a speed of at least 25 micrometres per second, in order to be able to bypass naturally occurring cervical mucus .
The movement pattern of sperm is also important. As sperm must traverse a long distance, those that move in a relatively straight line or in large circles have a much higher chance of successfully completing the journey . This is known as progressive motility.
On the other hand, sperm that swim around in small, tight circles, or simply vibrate in place, are much less likely to travel far enough to meet the egg. This is referred to as non-progressive motility .
It is important to note that not 100% of sperm in an ejaculation will be motile. In fact, a total motility rate (i.e. progressive and non-progressive motility combined) of 40% is considered normal .
Since progressive motility is required for conception, logic follows that is what we should pay attention to. According to the World Health Organisation, the threshold for progressive motility should be 32%, anything lower would be considered low sperm motility .
However, there is evidence that looking at total motility is a more relevant measurement of an individual’s sperm motility . Specifically, a total motile sperm count of over 20 million per ejaculate is considered normal. Between 5 million and 20 million total motile sperm count is considered low sperm motility, and anything less than 5 million is considered severely low sperm motility .
What causes low sperm motility, and how can it be treated?
Low sperm motility often overlaps with other causes of poor sperm health and/or male infertility. For example, poor sperm morphology (shape) can affect sperm motility, as can low sperm count (having lesser sperm cells equates to a lower total number of motile sperm) .
As such, some of the common causes of low sperm motility include [9, 10]:
- Testicular damage from injury or illness
- Enlarged scrotal veins
- Hormone imbalance
- Exposure to chemicals or environmental toxins
- Abuse of steroids
- Using recreational drugs, alcohol or tobacco
- Spending too much time sitting down
And accordingly, some tips for improving low sperm motility (and overall sperm health) are as follows.
Avoiding certain foods
While the exact reasons why aren’t yet clear, the quality of your diet can have a large impact on sperm health and male fertility.
In particular, consuming processed meats, trans fats, soy products and high-fat dairy products such as whole milk can lower sperm count (and by extension, sperm motility) as well as decrease overall sperm quality .
As such, avoiding or limiting your intake of these foods may be helpful in enhancing sperm motility.
Avoiding pollutants and toxins 
Exposure to cigarette smoke, pesticides, plastics in food and other environmental toxins are thought to affect sperm health and motility.
These chemicals can lower sperm count or damage sperm DNA (leading to misshapen sperm that can’t swim properly). Some can also mimic the effects of oestrogen in the body, creating a hormonal imbalance.
Eliminating exposure to such environmental toxins may help improve sperm motility.
Increasing exercise and physical activity 
A 2017 study found that overweight men who exercised for at least 50 minutes 3 times a week for over 16 weeks saw improved sperm health. Improvements in progressive motility, normal morphology and sperm concentration were observed.
Adding supplements to your diet 
There are several health supplements that have been shown to help improve sperm health and male fertility, and including them into your diet in appropriate doses may be beneficial in treating low sperm motility.
Some promising ones include zinc, selenium, L-carnitine, and vitamins C and E.
In particular, a 2019 study found that taking between 200mg to 400mg of CoQ10 supplement per day resulted in higher sperm concentration and motility after three months.
How can I find out if I have low sperm motility?
Low sperm motility may be present if there is failure to produce pregnancy despite regular, unprotected sex.
Since, as noted above, low sperm motility is often linked to other sperm issues, it may be prudent to consult a fertility specialist and take a definitive look at your overall sperm health.
This may be accomplished with a full-spectrum semen analysis covering various important parameters, such as semen volume, sperm concentration, sperm morphology, etc. — in addition to sperm motility .
Conclusion: Can I get pregnant with low sperm motility?
Getting pregnant requires (among other things) sperm that can literally go the distance, and low sperm motility can certainly pose a challenge to those TTC. However, low sperm motility need not mean that pregnancy is permanently off the table.
We know that sperm have to make a long journey, and that only a small number of sperm actually make it to the egg . If that’s the case, would it help if we somehow shortened the journey for sperm, while also making sure a larger number of them stay in the race?
One way to help more sperm get to the where it's needed is with the twoplus Fertility Applicator Extra. This at-home insemination kit lets you deposit sperm safely and conveniently higher up the vaginal tract, bypassing its acidic environment.
Another strategy is to reduce sperm loss through leakage after sex, by using our Sperm Guide. Safe, comfortable and tested for bio-compatibility with sperm, this medical-grade conception device helps prevent semen backflow and removes the need for awkward leg raises.
While the tips shared in this article, and the use of certain products, may help you overcome low sperm motility, it is important to remember that the condition is just one of many contributing causes of infertility.
If you’ve been facing trouble conceiving for more than 6 months, the best course of action is to schedule a fertility checkup with your healthcare provider to get a clear diagnosis and work out a medically sound treatment plan.
Are you taking too long to conceive? Check out our Getting Pregnant 101 Guide for must-know TTC tips below & above 35 years old.