How Is Sperm Motility Examined?

By BSc, MSc (embryologist), (gynecologist), BSc, MSc (embryologist), BSc, MSc (embryologist) and (invitra staff).
Last Update: 04/23/2020

Sperm that show low motility or are immobile are not able to reach the egg to fertilize it, so sperm mobility is a fundamental sperm quality parameter to achieve a natural pregnancy.

It is analyzed through a semen analysis report and is considered to be altered when the number of progressively motile spermatozoa is less than 32% or the total number of motile spermatozoa in the ejaculate is less than 40%.

Thanks to in vitro fertilization (IVF) treatments, it is possible to achieve pregnancy despite reduced seminal mobility, even in cases where only live, immobile sperm are present.

Sperm motility analysis

Sperm motility is assessed by a semen analysis called seminogramo semen analysis report. To perform this analysis, the male must provide the andrology laboratory with a semen sample in an approved vial with his name on it. It will be obtained by masturbation after 3-5 days of sexual abstinence.

With this sample, the movement of the sperm will be studied under the microscope by analyzing a small drop in Makler's or Neubauer's camera.

When carrying out this study, it is not only important to know whether they move or not, but also to analyze the way they move. Thus, firstly, the total percentage of mobile and immobile spermatozoa is analyzed and, secondly, the movement of mobile spermatozoa is specified:

is analysed whether the mobility is progressive or not. If the sperm do not manage to advance in distance, crossing the female reproductive system to reach the egg will be very complicated.
Form of movement
is indicated if the sperm move in a straight line or in a circle or zigzag.
is noted whether the movement is fast or slow.

It is also possible to calculate the total number of viable spermatozoa in the ejaculate, i.e. the living spermatozoa, both mobile and immobile.

It is important to note that not all laboratories perform the seminogram in the same way concerning motility. Some centers only distinguish between mobile and immobile spermatozoa, and others that are more detailed and indicate whether the movement is progressive, rapid, or rectilinear.

Considering undergoing a fertility treatment? By getting your individual Fertility Report your will see different clinics especially selected for you out of the pool of clinics that meet our strict quality criteria. Moreover, it will offer you a comparison between the fees and conditions each clinic offers in order for you to make a well informed choice.

Types of sperm mobility

Although not all assisted reproduction centers use it, there is a classification of sperm mobility based on the parameters mentioned above:

Motility type A or grade 3 (+++)
group of spermatozoa with progressive, rapid and rectilinear mobility.
Motility type B or grade 2 (++)
sperm move progressively but slowly.
Motility type C or grade 1 (+)
the motility of the sperm is slow and undisturbed. No progression is observed, but they move over the same position.
Motility type D or grade 0
this is the group of static or immobile spermatozoa, both living and dead.

When do you speak of motility problems?

The pathology associated with sperm mobility is called asthenozoospermiaor asthenospermia. It is defined as a sperm alteration characterized by low sperm motility.

According to the reference values of seminal quality established by the WHO (World Health Organization), a man suffers from asthenozoospermia when the number of progressively motile spermatozoa (type A + B) is less than 32% and when the total number of motile spermatozoa in the ejaculate (type A+B+C) is less than 40%.

This alteration can be a reason for infertility and is therefore considered a male fertility problem.

Various alterations lead to the appearance of spermatozoa mobility problems. You can read them here: Causes of Astenozoospermia.

However, on many occasions, this pathology is of unknown origin and has no specific treatment. In these cases, treatment to improve sperm motility is based on administering antioxidants, such as vitamins C and E.

Sperm Vitality and Mobility

As we have mentioned before, mobility is not always related to vitality. Although dead sperm can't move, not all sperm that don't move are dead. Therefore, there are live, immobile sperm that, although not viable for natural pregnancy, could be used to fertilize eggs by intracytoplasmic sperm injection (ICSI).

Therefore, it is possible to have children even with asthenozoospermia, as long as we find living sperm among the immobile ones.

As embryologist Laura Mifsud comment on:

In cases of severe asthenozoospermia, the most appropriate technique would be in vitro fertilization with ICSI, which consists of introducing a spermatozoon into an oocyte to ensure fertilization.

There are tests, such as the eosin test or the hypo-osmotic test, which detect the vitality of spermatozoa that do not move and allow us to distinguish between those spermatozoa that do not move due to deterioration or failure of their mobility machinery and those that do not show movement because they are dead.

You can learn more about these analyses by accessing the following link: Sperm vitality tests.

Kartagener's Syndrome

There is a pathology related to sperm mobility called Kartagener's syndrome. This is an unusual disease in which all the sperm are immobile but not all of them are dead.

The lack of mobility is due to an alteration in which the cells do not present ciliary movement, but whoever suffers it suffers its consequences in the respiratory tract so that one is aware of its condition before the search for pregnancy.

Although there is currently no definitive solution for this syndrome, pregnancies have been described using the ICSI technique in cases of patients who suffer from it, so they can be parents.

FAQs from users

What happens when there are problems with sperm motility?

By Dr. Mónica Aura Masip (gynecologist).

When there are mobility problems in the sperm, we speak in medical terms of asthenozoospermia. So, the higher the percentage of immobile or slow spermatozoa, the more difficult it is to achieve a natural pregnancy.

In most cases where there is an alteration in sperm motility, it will be more difficult for the sperm to travel all the way to reach the egg and fertilize it. Therefore, it will be necessary for those patients with asthenozoospermia to resort to some assisted reproduction technique to achieve pregnancy. Specifically, the most appropriate treatment would be in vitro fertilization (IVF).
Read more

Can immobile sperm be alive?

By Rebeca Reus BSc, MSc (embryologist).

Yes. In fact, even though they are not considered to be of good quality, live immobile sperm can be used to fertilize the eggs through ICSI if there is no motility available.

What is lazy sperm?

By Rebeca Reus BSc, MSc (embryologist).

Colloquially, we speak of lazy sperm when we refer to those with low motility because they are slow.

In some cases, natural pregnancy can be achieved with lazy sperm, but in others, it may be necessary to resort to assisted reproduction treatments to achieve this, especially if there are few motile sperm.

Suggested for you

As we have mentioned, the alteration of sperm mobility is called asthenozoospermia. In this link you can find more information about this one: Definition, causes and treatment of asthenozoospermia.

Sperm mobility is analysed by means of a spermobiogram. If you want to know more about this test, we recommend that you read the following article:

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Authors and contributors

 Laura Mifsud Elena
Laura Mifsud Elena
BSc, MSc
Bachelor's Degree in Biology from the University of Valencia (UV). Master's Degree in Biomedical Research from the University of Valencia, and another Master's Degree in Medicine and Reproductive Genetics from the Miguel Hernández University of Elche. Large experience working as an embryologist and head of laboratory at the Quirónsalud Hospital of Valencia, Spain. More information about Laura Mifsud Elena
Dr. Mónica  Aura Masip
Dr. Mónica Aura Masip
Dr. Mónica Aura has a degree in Medicine and General Surgery from the Autonomous University of Barcelona (UAB). She is also a specialist in Gynecology and Obstetrics from the Hospital de Santa Creu y Sant Pau and has a Master's degree in Human Assisted Reproduction from the University Juan Carlos I of Madrid and another in Health Center Management from the UB. More information about Dr. Mónica Aura Masip
Licence number: 31588
 Neus Ferrando Gilabert
Neus Ferrando Gilabert
BSc, MSc
Bachelor's Degree in Biology from the University of Valencia (UV). Postgraduate Course in Biotechnology of Human Assisted Reproduction from the Miguel Hernández University of Elche (UMH). Experience managing Embryology and Andrology Labs at Centro Médico Manzanera (Logroño, Spain). More information about Neus Ferrando Gilabert
 Rebeca Reus
Rebeca Reus
BSc, MSc
Degree in Human Biology (Biochemistry) from the Pompeu Fabra University (UPF). Official Master's Degree in Clinical Analysis Laboratory from the UPF and Master’s Degree about the Theoretical Basis and Laboratory Procedures in Assisted Reproduction from the University of Valencia (UV). More information about Rebeca Reus
Adapted into english by:
 Romina Packan
Romina Packan
inviTRA Staff
Editor and translator for the English and German edition of inviTRA. More information about Romina Packan

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