Mycoplasma Infection

Mycoplasma infection is an infection caused by a group of very small bacteria called Mycoplasma. These organisms can affect different parts of the body, including the lungs, urinary tract, reproductive tract, and genitals. In men’s health, mycoplasma infection matters because certain species may be linked to urethritis, pelvic or genital symptoms, and in some cases fertility concerns such as inflammation, semen quality changes, or infection in the reproductive tract.

Not every positive test means a serious illness, and not every mycoplasma species behaves the same way. Some are clearly associated with disease, while others may be found in the body without causing symptoms. That makes proper testing, interpretation, and treatment decisions important.

Table of Contents

• Key takeaways
• What is mycoplasma infection?
• Types of mycoplasma that matter in men’s health
• Why mycoplasma infection matters for men and fertility
• Causes and how it spreads
• Symptoms and signs
• What’s normal vs what’s not?
• Testing and diagnosis
• How to understand test results
• Possible effects on sperm and fertility
• Treatment options
• Sex partners, reinfection, and prevention
• When to see a doctor
• Questions to ask your doctor
• Related tests and terms
• FAQ
• References

Key takeaways

• Mycoplasma infection is not one single disease; it refers to infections caused by different Mycoplasma species.
• Mycoplasma genitalium is one of the most important genital species and is a recognized cause of nongonococcal urethritis in men.
• Some mycoplasmas may be present without symptoms, so a positive test does not always equal clinically meaningful infection.
• Symptoms can include burning with urination, urethral discharge, pelvic discomfort, testicular pain, or no symptoms at all.
• PCR or nucleic acid amplification testing is commonly used because these organisms can be difficult to grow in routine culture.
• Treatment depends on the specific organism and possible antibiotic resistance; not all standard antibiotics work.
• In some cases, genital tract infection or inflammation may affect semen quality or fertility, but the relationship is not always straightforward.
• If symptoms persist, recur, or affect fertility plans, a clinician should evaluate for sexually transmitted infections, prostatitis, epididymitis, and other causes.

What is mycoplasma infection?

Mycoplasma infection refers to illness caused by bacteria in the Mycoplasma group. These organisms are unusual because they lack a cell wall. That detail matters medically: antibiotics that normally work by targeting the bacterial cell wall, such as penicillins, are generally not effective against mycoplasma.

The term is broad. It can refer to:

• Respiratory infection, especially from Mycoplasma pneumoniae, a cause of atypical pneumonia or “walking pneumonia”
• Genitourinary infection, including urethritis or reproductive tract infection linked to species such as Mycoplasma genitalium
• Colonization, where an organism is detected but may not be causing disease

For men researching fertility, sexual health, or semen testing, the most relevant question is usually not “what is mycoplasma in general?” but rather: which mycoplasma species was found, where was it found, and is it likely to be causing symptoms, inflammation, or reproductive problems?

Types of mycoplasma that matter in men’s health

Several organisms are commonly discussed under the “mycoplasma” umbrella, but they are not interchangeable.

Organism	Main area affected	Why it matters	Common clinical relevance in men
Mycoplasma genitalium	Genitourinary tract	Recognized sexually transmitted pathogen	Nongonococcal urethritis, persistent urethral symptoms, possible genital tract inflammation
Mycoplasma hominis	Genitourinary tract	Can be detected in the genital tract; significance varies	May be associated with genitourinary infection in some settings, but interpretation can be complex
Ureaplasma urealyticum / Ureaplasma parvum	Genitourinary tract	Related organisms often discussed alongside mycoplasma	Sometimes linked to urethritis or fertility concerns, though may also be present without symptoms
Mycoplasma pneumoniae	Respiratory tract	Cause of atypical pneumonia	Usually not a fertility issue; more relevant for cough, fever, chest symptoms

In sexual medicine and fertility consultations, Mycoplasma genitalium is usually the main pathogen of interest. It has clearer evidence as a cause of urethritis and persistent or recurrent genital symptoms.

Why mycoplasma infection matters for men and fertility

Mycoplasma infection can matter for several reasons:

• It may cause urethritis, meaning inflammation of the urethra, often felt as burning, stinging, discharge, or irritation.
• It can be persistent. Some infections do not clear easily and may not respond to first-line antibiotics if resistance is present.
• It may affect the reproductive tract. Inflammation involving the prostate, epididymis, or semen can potentially interfere with fertility, though this is not true in every case.
• It can be asymptomatic, which means transmission may occur without obvious warning signs.
• It often overlaps with STI evaluation. Men with symptoms may also need testing for chlamydia, gonorrhea, trichomonas, and other causes of urethritis.

For men trying to conceive, infection-related inflammation is important because sperm function depends on a stable, low-inflammatory environment. Fever, active infection, white blood cells in semen, oxidative stress, and genital tract inflammation can all potentially influence sperm count, motility, morphology, DNA integrity, or comfort during ejaculation.

Causes and how it spreads

The cause depends on the species:

Genital mycoplasma infection

Genital infections, especially those caused by Mycoplasma genitalium, are generally spread through sexual contact. This may include vaginal or anal sex, and possibly other forms of intimate genital contact. Transmission risk can increase with:

• New or multiple sexual partners
• Unprotected sex
• A prior history of sexually transmitted infections
• Sex with a partner who has symptoms or an untreated infection

Respiratory mycoplasma infection

Mycoplasma pneumoniae spreads through respiratory droplets, usually in close-contact settings like households, schools, military barracks, and workplaces.

Can mycoplasma be present without causing disease?

Yes. Some organisms in the genital tract, especially species other than Mycoplasma genitalium, may sometimes be detected in people without symptoms. That is one reason clinicians interpret results based on:

• The exact organism identified
• Symptoms
• Test site
• Signs of inflammation
• Fertility concerns or reproductive symptoms
• Whether other more likely causes have been ruled out

Symptoms and signs

Symptoms vary a lot. Some men have clear symptoms; others have none.

Possible symptoms of genital mycoplasma infection in men

• Burning or pain with urination
• Urethral irritation or itching
• Clear, cloudy, or mucous-like penile discharge
• Pelvic discomfort
• Pain with ejaculation
• Testicular or scrotal discomfort
• Persistent symptoms after treatment for “nonspecific urethritis”

Possible fertility-related signs

• Abnormal semen analysis
• White blood cells in semen
• Recurrent genital tract inflammation
• Difficulty conceiving without an obvious explanation

Symptoms of respiratory mycoplasma infection

• Dry cough
• Fatigue
• Fever
• Sore throat
• Chest discomfort

Respiratory mycoplasma is generally a separate issue from genital mycoplasma. People often confuse them because they share the same broader bacterial family.

What’s normal vs what’s not?

There is no single “normal range” for mycoplasma infection in the way there is for a hormone or blood value. Instead, normal versus abnormal depends on symptoms, test results, and clinical context.

Situation	Often considered more reassuring	More concerning or abnormal
Urinary/genital symptoms	No symptoms, no signs of inflammation	Burning, discharge, pelvic pain, recurrent urethritis
Mycoplasma test result	No pathogen detected, or organism detected with unclear significance and no symptoms	Mycoplasma genitalium detected in a symptomatic patient
Semen findings	Normal semen parameters and no inflammatory signs	Leukocytes in semen, abnormal motility, unexplained fertility issues, infection symptoms
After treatment	Symptoms resolve and clinician confirms no further concern	Persistent symptoms, recurrent infection, suspected antibiotic resistance, possible reinfection

If you are looking at a lab report and see a mycoplasma species listed, the right question is not only “is it positive?” but also “does this finding explain my symptoms or fertility issue?”

Testing and diagnosis

Testing depends on the suspected infection site and the organism being considered.

How genital mycoplasma is tested

For genital symptoms, the most useful tests are typically nucleic acid amplification tests (NAATs) or PCR-based tests. These look for the genetic material of the organism.

Samples may include:

• First-catch urine
• Urethral swab
• Sometimes rectal swab, depending on exposure and symptoms
• In selected fertility workups, semen testing may be used, though interpretation can vary by lab and clinical setting

Why ordinary culture may not be enough

Mycoplasmas are hard to culture in standard labs. That is why PCR-based testing is often preferred. It is faster and generally more sensitive for the clinically important genital species.

Other tests a clinician may order

• Chlamydia and gonorrhea testing
• Urinalysis and urine culture
• Trichomonas testing in selected cases
• Semen analysis if fertility is a concern
• Semen culture or inflammatory workup in certain fertility or urology settings
• Evaluation for prostatitis, epididymitis, or pelvic floor dysfunction if symptoms are ongoing

When testing is most helpful

1. You have urethral symptoms such as discharge or burning with urination.
2. You have persistent or recurrent nongonococcal urethritis.
3. You have a partner diagnosed with a relevant STI.
4. You have unexplained genital tract inflammation or fertility concerns and your clinician thinks infection could be contributing.

How to understand test results

Test interpretation depends on the species, location, and symptoms.

If Mycoplasma genitalium is positive

This is generally considered clinically meaningful, especially if you have urethritis symptoms. It is a recognized sexually transmitted pathogen and often warrants treatment guided by current recommendations and, when available, resistance testing.

If Mycoplasma hominis or other genital organisms are positive

The result may be harder to interpret. In some men these organisms may be associated with infection or inflammation, but in others they may be incidental findings. Your clinician may weigh:

• Whether you have symptoms
• Whether there are white blood cells or inflammatory signs
• Whether there are semen abnormalities
• Whether other causes are more likely

If the test is negative but symptoms continue

A negative mycoplasma test does not rule out all causes of urethral or pelvic symptoms. Persistent symptoms may be due to:

• Chlamydia or gonorrhea
• Trichomonas
• Chronic prostatitis or chronic pelvic pain syndrome
• Epididymitis
• Urinary tract infection
• Irritation from soaps, lubricants, or friction
• Pelvic floor muscle dysfunction

Possible effects on sperm and fertility

This is one of the most searched aspects of mycoplasma infection, especially for men reviewing fertility testing. The short answer is: mycoplasma may affect fertility in some men, but the impact is variable and not always clear-cut.

How infection could affect fertility

Potential mechanisms include:

• Inflammation in the reproductive tract
• Oxidative stress, which can impair sperm function
• Changes in semen quality, such as lower motility or altered morphology in some studies
• Leukocytospermia, or white blood cells in semen
• Damage to the epididymis, prostate, or urethra in more significant or persistent infections

What the evidence suggests

Research has explored associations between genital mycoplasma or ureaplasma and:

• Reduced sperm motility
• Abnormal semen parameters
• Sperm DNA damage
• Male accessory gland infection or inflammation

But the strength of the evidence differs by organism. Mycoplasma genitalium has stronger evidence as a pathogen in urethritis. For other species, results are more mixed, and a positive test alone does not prove they are the cause of infertility.

When to think more seriously about infection in a fertility workup

• You have urinary or genital symptoms
• Your semen analysis shows inflammatory changes or unexplained abnormalities
• You have repeated failed conception without a clear explanation
• You have testicular, epididymal, or pelvic pain
• You have a history of STI or recurrent urethritis

Can treating mycoplasma improve sperm health?

Sometimes, especially if active infection and inflammation are present. If an infection is contributing to semen abnormalities, treatment and time may allow semen quality to improve. However, semen parameters do not usually change overnight. Because sperm development takes roughly 2 to 3 months, follow-up semen testing is often delayed for several weeks or months depending on the situation.

Treatment options

Treatment depends on the species identified, symptoms, resistance patterns, and local clinical guidelines.

Important antibiotic point

Because mycoplasma lacks a cell wall, antibiotics like penicillin or amoxicillin are generally not effective against it.

Common treatment approaches

Depending on the organism and resistance testing, clinicians may use antibiotics from categories such as:

• Macrolides
• Tetracyclines
• Fluoroquinolones

For Mycoplasma genitalium, treatment can be more complicated because antibiotic resistance, especially to macrolides, is a well-recognized issue. Current management may involve:

1. Testing to confirm the organism
2. Sometimes resistance-guided therapy if available
3. A staged antibiotic approach rather than a single simple dose in some cases
4. Follow-up planning if symptoms continue or reinfection is possible

Do all positive tests need treatment?

Not always. This depends heavily on:

• The exact species
• Whether you have symptoms
• Whether there is documented inflammation
• Whether fertility specialists or urologists believe the organism is clinically relevant

That is why self-treating based on an online lab result can be a mistake. Unnecessary antibiotics can make resistance worse and may not solve the real problem.

What to expect after treatment

• Symptoms may improve over days to weeks
• Sexual activity may need to be avoided for a period recommended by your clinician
• Partner evaluation or treatment may be necessary
• If symptoms persist, further testing may be needed to check for resistance, reinfection, or another diagnosis

Sex partners, reinfection, and prevention

When genital mycoplasma infection is sexually associated, partner management matters. Otherwise, one person may be treated while the infection continues to circulate between partners.

Practical prevention steps

• Use condoms consistently, especially with new partners
• Avoid sex until treatment guidance has been completed, if advised by your clinician
• Make sure partners are informed and tested or treated when appropriate
• Seek evaluation for persistent or recurrent symptoms rather than repeating antibiotics on your own

Can you get it again?

Yes. Reinfection is possible if a partner remains untreated or if there is exposure to a new infected partner. A repeat positive test can represent treatment failure, resistance, or reinfection, which is why follow-up is sometimes important.

When to see a doctor

You should consider medical evaluation if you have:

• Burning with urination
• Penile discharge
• Pelvic, scrotal, or testicular pain
• Pain with ejaculation
• Symptoms after a partner is diagnosed with an STI
• Persistent symptoms after prior STI treatment
• Abnormal semen analysis with possible signs of inflammation
• Difficulty conceiving and concern about infection or prior STI exposure

Seek more urgent care if you have severe testicular pain, high fever, significant swelling, inability to urinate, or symptoms of acute infection that are rapidly worsening.

Questions to ask your doctor

• Which mycoplasma species was found on my test?
• Do you think this result is actually causing my symptoms?
• Should I also be tested for chlamydia, gonorrhea, trichomonas, or prostatitis?
• Do I need treatment now, or could this be colonization rather than infection?
• Is resistance testing available for Mycoplasma genitalium?
• Should my partner be tested or treated?
• Could this affect my fertility or semen analysis?
• When should I repeat testing or follow up if symptoms do not improve?

Related tests and terms

If you are researching mycoplasma infection, you may also come across these related terms:

Term	What it means	Why it matters
Nongonococcal urethritis (NGU)	Urethritis not caused by gonorrhea	Mycoplasma genitalium is a known cause
PCR / NAAT	Molecular test that detects bacterial genetic material	Main way genital mycoplasma is diagnosed
Leukocytospermia	High white blood cells in semen	May suggest inflammation or infection
Semen analysis	Measures sperm count, motility, morphology, and more	Useful if fertility is a concern
Epididymitis	Inflammation of the epididymis	Can cause scrotal pain and may affect fertility if significant
Prostatitis	Inflammation or infection involving the prostate	May overlap with pelvic pain and urinary symptoms

Common misconceptions

“A positive mycoplasma test always means I have an STI.”

Not always. Some species are sexually associated and clinically important, especially Mycoplasma genitalium. Others can be harder to interpret and may not always represent active disease.

“If I have no symptoms, it can’t matter.”

Not necessarily. Some genital infections can be asymptomatic. That said, asymptomatic detection does not always mean treatment is needed. Clinical context matters.

“Standard antibiotics will take care of it.”

Not always. Mycoplasma lacks a cell wall, so many common antibiotics do not work. Resistance is also a real issue for some species.

“Any mycoplasma finding explains infertility.”

This is too simplistic. Infection may contribute in some men, but infertility usually requires a broader evaluation that includes semen analysis, hormones, anatomy, lifestyle factors, and female partner factors.

Frequently asked questions

Is mycoplasma infection an STI?

Some forms are. Mycoplasma genitalium is considered a sexually transmitted pathogen. Other mycoplasma-related organisms may be found in the genital tract but are not always interpreted the same way.

Can mycoplasma infection cause infertility in men?

It can be associated with inflammation and semen changes in some men, which may affect fertility. But a positive result does not automatically mean it is the main cause of infertility.

What are the symptoms of mycoplasma genitalium in men?

Common symptoms include burning with urination, urethral irritation, penile discharge, and sometimes pelvic or testicular discomfort. Some men have no symptoms.

Can you have mycoplasma without symptoms?

Yes. Asymptomatic infection or colonization is possible, depending on the organism and site tested.

How is mycoplasma infection diagnosed?

Diagnosis is usually made with PCR or NAAT testing on urine or swab samples. Standard bacterial culture is often not sufficient.

What antibiotics treat mycoplasma infection?

Treatment depends on the organism and resistance pattern. Clinicians may use macrolides, tetracyclines, or fluoroquinolones, but the best option varies case by case.

Does amoxicillin or penicillin treat mycoplasma?

No. These antibiotics generally do not work against mycoplasma because the organism does not have a cell wall.

Should my partner be treated too?

Possibly. If the infection is sexually associated, partner testing or treatment may be recommended to reduce reinfection risk. This should be guided by a clinician.

Can mycoplasma come back after treatment?

Yes. Recurrence can happen due to reinfection, incomplete eradication, or antibiotic resistance, especially with Mycoplasma genitalium.

Should I get tested for mycoplasma during a fertility workup?

Sometimes, especially if you have genital symptoms, leukocytes in semen, recurrent inflammation, a history of STI, or unexplained infertility. It is not automatically necessary for every man.

References

• Centers for Disease Control and Prevention (CDC). Sexually Transmitted Infections Treatment Guidelines, including guidance on Mycoplasma genitalium.
• CDC. Mycoplasma pneumoniae infection information.
• European guideline on the management of Mycoplasma genitalium infections.
• American Urological Association (AUA) resources related to male infertility and urogenital infection evaluation.
• World Health Organization (WHO). Laboratory manual for the examination and processing of human semen.
• Peer-reviewed reviews on genital mycoplasmas, urethritis, and male infertility in journals such as Clinical Microbiology Reviews, The Lancet Infectious Diseases, and reproductive medicine journals.