What Are the Causes of Teratozoospermia?

By BSc, MSc (embryologist).
Last Update: 11/26/2018

Teratozoospermia or teratospermia is the medical term for the presence of an abnormal sperm morphology in the ejaculate of males.

This sperm disorder affects sperm quality, leading to male infertility or sterility, and reducing their chances of conceiving.

The particular causes of teratozoospermia are unknown in the vast majority of cases. However, there exist certain factors that can affect the semen by causing abnormal sperm morphology.

Defective spermatogenesis

Most experts agree that sperm morphology alterations occur during the final phase of sperm formation (i.e. spermatogenesis).

Spermatogenesis is the process whereby sperm production takes place. It occurs in the testicles and can take up to 3 months.

Particularly, spermiogenesis, which is the final stage of spermatogenesis, where sperm already contain all their genetic material, is the stage where sperm go through the maturation process, acquiring their characteristic morphology.

When sperms already have an oval-shaped head and the tail fully formed, they are released to the seminiferous tubules so they can continue their pathway.

In short, it is only natural that any kind of defect or abnormality that occurs during spermatogenesis causes sperm abnormalities in the head, neck, and/or tail.

Treatable teratozoospermia

Teratozoospermia can be reversible or irreversible depending on what is causing it.

As regards treatable or reversible teratozoospermia, the good news is that males affected by it can recover their fertility in a few months after having followed the appropriate treatment.

To check if it has been successful, one should repeat the semen analysis and compare it with the previous one.

The following are the most common causes of reversible teratospermia:


As surprising as it may seem, lifestyle affects sperm quality to a large extent.

Especially if one is stressed or anxious, sperm morphology can worsen, aside from other parameters such as sperm count and motility.

Alcohol, tobacco, and street drug use are associated with sperm disorders, too.

Continuous testicular exposure to heat affects spermatogenesis as well. For example, placing the laptop on your lap, wearing too tight clothes, or prolonged car driving can cause teratozoospermia.

Finally, eating habits and sports can influence male fertility as well.

Males who are currently trying to conceive with their partner should have healthy life habits, follow a balanced diet, practice sports on a regular basis, and avoid toxic substance use at all costs.

Seminal tract infections

Seminal tract infections are caused by invasive microorganisms, including bacteria and viruses, in the male reproductive tract.

Infectious agents can be present either in urine or sperm, causing sperm abnormalities, inflammations, and blockage in the seminal ducts.

Most common bacterial infections in the testes are chlamydia and gonorrhea. Fortunately, both can be overcome with antibiotics.

Get more info: Sperm Infections and Temporary Infertility.

Fever caused by the flu or any other condition may alter sperm production temporarily as well.


Sex hormones like testosterone, LH, FSH, and inhibin have a very important role in regulating spermatogenesis.

Thus, any alteration in the adequate levels of these hormones due to the administration of medications can impact spermatogenesis negatively.

As explained above, if the spermiogenesis phase is altered, sperms will not mature as expected, causing teratozoospermia.

Untreatable teratozoospermia

In cases of teratozoospermia, if no improvement is seen in the second sperm analysis report after being treated, it might be a case of irreversible teratospermia.

If this were the case, the couple may have no alternative but to undergo fertility treatment if they wish to become parents. Unfortunately, achieving a natural pregnancy with untreatable teratospermia is highly unlikely.

Furthermore, there exist certain conditions or circumstances that can cause long-term or untreatable teratospermia. The following are the most remarkable ones:

Cancer treatments

Chemotherapy and radiotherapy can alter sperm stem cells and spermatogenesis at the same time, causing severe teratozoospermia along with other serious disorders.

For this reason, all men suffering from cancer should consider retaining their fertility through sperm freezing. This way, they can have children in the future, after having overcome the disease.

If you are considering freezing your sperm to have a child in the future, we recommend that you start by creating a Fertility Report. In 3 simple steps, it will show you a list of clinics that fit your preferences and meet our strict quality criteria. Moreover, you will receive a report via email with useful tips to visit a fertility clinic for the first time.

Genetic abnormalities

One of the most complicated causes to detect. Normally, when the cause of teratozoospermia cannot be explained, it is attributed to genetic alterations.

Gene or chromosomal abnormalities in sperm are considered a serious defect, mainly because there is no possible way for them to be treated.

Teratozoospermia can be caused by diseases that affect the testes mainly, such as:

  • Trauma to the testicles, especially during childhood
  • Testicular varicocele
  • Meningitis
  • Diabetes mellitus

Aside from all this, age can affect sperm morphology as well. In particular, several studies have confirmed that, in males aged 45 or over, the rate of abnormal sperm in the semen increases.

FAQs from users

Does poor sperm vitality correlate with abnormal sperm morphology?

By Zaira Salvador BSc, MSc (embryologist).

Yes, teratozoospermia can affect both live and dead sperm.

Dead sperm do not have an abnormal morphology in all cases. Sometimes, they are confused with immotile sperm, and performing a dye test is necessary to determine whether they are actually viable or not.

Can leukocytospermia cause teratozoospermia and male infertility?

By Zaira Salvador BSc, MSc (embryologist).

Leukocytospermia or pyospermia is defined as having white blood cells in the semen, with a concentration that is above 1 million per milliliter. The cause of this sperm disorder is an infection in the seminal tract, which should be treated with antibiotics, as it can affect spermatogenesis (sperm production process), and lead to oligospermia or teratozoospermia.

Are teratozoospermia and asthenozoospermia caused by the same factors?

By Zaira Salvador BSc, MSc (embryologist).

In most of the cases, asthenozoospermia and teratozoospermia have the same causes. Both sperm parameters appear altered in the semen analysis, which is known as asthenoteratozoospermia. Nonetheless, they do not go hand in hand in all cases.

Suggested for you

The most important test to detect teratozoospermia in males is the semen analysis (SA). You may also enjoy some further information reading this: What Is a Semen Analysis Report?

Also, we have made reference to sperm freezing as an option for fertility preservation in males with cancer. If you want to delve deeper into it, we recommend that you have a look at this: What Is the Process of Freezing Sperm?

Our editors have made great efforts to create this content for you. By sharing this post, you are helping us to keep ourselves motivated to work even harder.


Aly JM, Polotsky AJ. Paternal Diet and Obesity: Effects on Reproduction. Semin Reprod Med. 2017;35(4):313-317.

Asare-Anane H, Bannison SB, Ofori EK, Ateko RO, Bawah AT, Amanquah SD, Oppong SY, Gandau BB, Ziem JB. Tobacco smoking is associated with decreased semen quality. Reprod Health. 2016;13(1):90.

Chemes HE. Phenotypic varieties of sperm pathology: Genetic abnormalities or environmental influences can result in different patterns of abnormal spermatozoa. Anim Reprod Sci. 2018;194:41-56.

Choe JH, Seo JT. Is Varicocelectomy Useful for Subfertile Men with Isolated Teratozoospermia? Urology. 2015 Dec;86(6):1123-8.

De Braekeleer M, Nguyen MH, Morel F, Perrin A. Genetic aspects of monomorphic teratozoospermia: a review. J Assist Reprod Genet. 2015;32(4):615-23.

Oumaima A, Tesnim A, Zohra H, Amira S, Ines Z, Sana C, Intissar G, Lobna E, Ali J, Meriem M. Investigation on the origin of sperm morphological defects: oxidative attacks, chromatin immaturity, and DNA fragmentation. Environ Sci Pollut Res Int. 2018;25(14):13775-13786.

Ray PF, Toure A, Metzler-Guillemain C, Mitchell MJ, Arnoult C, Coutton C. Genetic abnormalities leading to qualitative defects of sperm morphology or function. Clin Genet. 2017;91(2):217-232.

FAQs from users: 'Does poor sperm vitality correlate with abnormal sperm morphology?', 'Can leukocytospermia cause teratozoospermia and male infertility?' y 'Are teratozoospermia and asthenozoospermia caused by the same factors?'.

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Authors and contributors

 Zaira Salvador
Zaira Salvador
BSc, MSc
Bachelor's Degree in Biotechnology from the Technical University of Valencia (UPV). Biotechnology Degree from the National University of Ireland en Galway (NUIG) and embryologist specializing in Assisted Reproduction, with a Master's Degree in Biotechnology of Human Reproduction from the University of Valencia (UV) and the Valencian Infertility Institute (IVI) More information about Zaira Salvador
License: 3185-CV

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  1. Featured

    Hi Doctor, just want to know if alcohol consumption is related teratozoospermia, is it reversible or not?


    • Hello David,

      Yes, progressive deterioration in sperm quality is associated with alcohol intake. So you can have an idea, the influence of alcohol consumption on semen quality has a dose-effect and also time-effect relationship.

      This means that a man’s sperm volume, sperm vitality, and sperm survival rate negatively correlate with the amount of alcohol he drinks. In a study conducted on 100 alcoholics, teratozoospermia, oligozoospermia, and their combined presence were double or more amongst alcoholics.

      I hope I have been able to help,


  2. Featured


    A sperm analysis test done about 2 years ago showed a count of abt 21.6 mil/ml with 2.3 ml as total volume and normal morphology. Recent test done 2 days ago, showed count as unchanged (21 mil/ml), however morphology result indicated teratozospermia. Is the new test erroneous? Or can teratozospermia develop over time?
    Thank you.

    • Hello Mark,

      Yes, sperm pathologies or alterations in the sperm parameters can appear over time for a number of reasons, such as changes in eating habits (eating more or less than usual), smoking, drug consumption, certain medical treatments…

      Should you have any further doubt, do not hesitate to ask.

  3. Featured

    Hi, I have an severe addiction to masturbation (daily once at night), though married for 9 years. For this reason, I do intercourse with wife only at the time of ovulation (1 or 2 times), however, couldn’t achieve pregnancy. My recent semen test was diagnosed with Astheanozoospermia result. Is it because of strong masturbation addiction or other reason? I am non-alcoholic and non-smoker as well.
    Appreciate a reply.

    • Dear Akash,

      Masturbation has no influence on having asthenozoospermia or not. If you want to learn more about the causes of this sperm alteration, visit the following post: Asthenozoospermia.

      Hope this helps,


  1. Omsak

    I’m 32 years, 5ft 10 inches tall, weighing 112kg and these are the results after 3 days of abstinence are below. The numbers on the 3rd row are WHO guidelines.

    Time of collection 01:00PM
    Time of examination 02:21PM
    Physical Examination
    Colour Whitish Whitish
    Volume (ml) 3.0 > or = 1.5
    Liquefaction 30 Mins Within 30 Mins
    Fructose Test Positive Positive
    pH Alkaline Alkaline
    Microscopic Examination
    Sperm Concentration (M/ml) 18 > or = 15
    Total Sperm count (M/ ejaculate) 54 > or = 39
    Morphology (% Normal) 01 > or = 04
    Vitality (% Live) 50 > or = 58
    Motility within 1 hour of ejaculation
    Total Motility (PR+NP,%) 45 > or = 40
    Progressive motility (PR,%) 35 > or = 32
    Pus cells 1-3 /HPF
    RBCs Occasional /HPF
    Epithelial Cells 0-2 /HPF
    Agglutinates Nil
    Aggregates Nil

    Can you kindly comment of the degree of infertility. Thanks.

  2. AD


    My SO’s semen analysis has high sperm concentration and total motility of 143 x 10^6. But morphology is only 3% normal. Do you think this may affect chances of natural conception? Is there a compensation for low morphology and low motility by high sperm count?

    The detailed results are as follows:
    Volume: 3ml.
    Semen Concentration: 148 x 10^6
    % progressive motility: 32% ; Non progressive 0%
    Total Motile: 143.86 x 10^6
    Normal Morphology: 3%
    Predominant abnormal: 39% Pyriform heads.
    Comments: Asthenoteratozoospermia

    I am 47 and given my age, we need to make the most of every cycle…

    Thank you!

  3. Noor-Ul-Ain

    Hello my husband is suffering from insulin dependent diabetes since 2014 (neuropathies included) .we just got his result back and he has 94% head abnormalities 3% normal form.what are the chances that these abnormalities can be reversed?
    P.s:- what are our options now?

  4. sabor

    Hi madam,
    Thanx in advance for your attention. After a 50 hour gap of last intercourse I performed my sperm test… Sperm volume is 1 ml and sperm concentration is normal but motility is low poor motile are 60 per cent and moderate motile are 40 percent but there is a total absence of good and excellent progression sperm… Also, I have had some hard time for the last 6 months n suffering in stress. I’m a smoker and occasionally drink alcohol… need your kind advise… plz

  5. haytham el saeid

    I am 26 years old, not married and I did a seminogram (semen test ) for check up. I did the 1st semen test on 4 August 2016 and volume was 3.2 ml, sperm count= 13 million per mm, total sperm count 41 600 000, motility 50 % i-ii, morphology 60 % normal (hypospermia).

    O made another test at 26 August 2016, and volume become 4.5, sperm count 58 million per mm, total sperm count 261 000 000 motility 70%, 20% no progressive 10% immobile, but morphology 1% normal and 99% not normal (teratozoospermia).

    And the 2nd test was made in 2 different laboratories in Barcelona. So, please help me… what should I do or what is meant by this? Is there a problem or what do you advise me to do as I am very worried?

    Is this normal or not? I mean the changes in the tests.

    Thanks a lot