This page is general health information, not medical advice. It cannot tell you whether you have an infection. A clinician can, and the testing options on this site are a good place to start.

Mycoplasma genitalium is a sexually transmitted bacterium that many people have never heard of. It rarely appears on a standard STD panel. Some clinicians order the test only when symptoms keep coming back.

This guide explains what the organism is, what the research suggests, how the CDC approaches testing and treatment, and how to ask about it in Los Angeles. A clinician can answer questions about your own situation. The sections below cover the general picture.

What mycoplasma genitalium is

Mycoplasma genitalium is a very small bacterium. It belongs to a group of bacteria that have no cell wall. That detail matters in practice. Many common antibiotics work by attacking the cell wall, so they do not work against this organism.

Research suggests the bacterium lives on the lining of the urinary and genital tracts. It is spread through sexual contact. It is also found in the rectum in some people. The CDC STI Treatment Guidelines (2021) describe it as an STI that is increasingly recognized and that is not well known to the public.

The “composition” question

This is an infection, not a substance, so there are no ingredients or compounds to list. What can be described is the biology. It is a bacterium with an unusually small genome and no cell wall. Those traits help explain why it is hard to grow in a lab and why it is treated differently from chlamydia or gonorrhea.

Mycoplasma genitalium symptoms

Many people with this infection have no symptoms. That is why the topic can feel confusing. A person cannot tell from how they feel whether it is present.

When mycoplasma genitalium symptoms do appear, the CDC guidelines link the organism to a few conditions:

Urethritis, which is inflammation of the urethra. It can cause burning with urination or discharge from the penis.
Cervicitis, which is inflammation of the cervix. It can cause unusual discharge or bleeding between periods or after sex.
Pelvic inflammatory disease (PID), an infection of the upper reproductive tract. The CDC says research suggests an association, and the evidence is still developing.

These symptoms overlap closely with chlamydia and gonorrhea. Many other conditions can cause them too. For that reason, symptoms alone cannot point to a cause. A test and a clinician visit can. If you want to read about the infection that most often comes up first in this situation, see our guide to chlamydia symptoms, testing and treatment in Los Angeles.

When the CDC recommends testing

The CDC STI Treatment Guidelines (2021) do not recommend routine screening for mycoplasma genitalium in people who have no symptoms. The CDC also does not recommend testing people who have no symptoms just because a partner has had it, unless a clinician advises otherwise for a specific reason.

Instead, the CDC suggests considering testing in specific situations:

Persistent or recurrent urethritis. This means symptoms that continue or return after a clinician has already treated the more common causes.
Persistent or recurrent cervicitis. The same idea applies when the cervix remains inflamed after the usual causes have been addressed.
Contacts of a person with a confirmed infection. The guidelines describe testing sex partners of someone diagnosed with mycoplasma genitalium, and a clinician decides what makes sense.

The guidelines also discuss testing in certain cases of PID. Your clinician is the right person to decide whether it applies to you.

Why it is not on a standard panel

A typical STD panel covers chlamydia, gonorrhea, syphilis and HIV. Those are the infections where the CDC and the U.S. Preventive Services Task Force recommend screening for defined groups of people. Mycoplasma genitalium is not in that group, because routine screening of people without symptoms has not been shown to help.

There is a second reason, which is the testing method. The CDC guidelines describe nucleic acid amplification tests (NAATs) as the way to detect it. An FDA-cleared test became available in recent years, but not every clinic or lab offers one. A test may also need to be ordered on purpose, with a sample such as urine, a vaginal swab or a cervical swab.

The CDC does not publish a window period for mycoplasma genitalium in its guidelines. If you are asking about timing after a possible exposure, that is a question for your clinician.

Why resistance-guided treatment matters

This is the part of the research that sets mycoplasma genitalium apart. The CDC guidelines note that the bacterium has become resistant to some of the antibiotics clinicians have used for it. Resistance to the macrolide group of antibiotics is common, and resistance to other groups has also been reported.

For this reason, the CDC recommends resistance-guided therapy where it is available. In plain terms, the lab checks the sample for genetic markers of macrolide resistance. The clinician then chooses a medicine based on that result. Treatment is something only a clinician prescribes. This guide does not describe doses or schedules, and you should not use leftover or borrowed antibiotics.

Research suggests that it can take more than one step to clear the infection, and a clinician may plan a follow-up. Mycoplasma genitalium is a bacterial infection, and bacterial infections can be treated. Resistance can make the path less direct than it is for some other STIs.

Safety profile and what to ask about

The usual safety concerns here apply to treatment choices, not to the test itself. A urine or swab test is low risk. For medicines, a clinician weighs your medical history, other medicines you take, pregnancy and any allergies. Tell the clinician about all of these before anything is prescribed.

Some points are worth raising at a visit:

If you could be pregnant or are pregnant, say so. Some antibiotics are chosen differently during pregnancy.
If you have had symptoms for a while, say how long, and what treatment you have already tried.
If you take PrEP or have used doxy-PEP, mention it. The CDC’s 2024 doxy-PEP guidance focuses on chlamydia, gonorrhea and syphilis, so ask your clinician how it relates to your situation.
Ask whether your sex partners should be seen as well. Clinicians often recommend this so that the infection is not passed back and forth.

Left untreated, research suggests mycoplasma genitalium may be linked to complications such as PID in some people. Evidence on longer-term effects, including fertility, is still limited. That is a reason to get persistent symptoms looked at. It is not a reason for alarm.

Quality indicators: how to judge a test and a clinic

There is no product to buy here, but you can still judge the quality of the care you get. These are reasonable things to look for:

A clinician-ordered test. The test is ordered and the result is explained by a licensed clinician who can act on it.
A NAAT method. This is the testing type the CDC guidelines describe for mycoplasma genitalium.
Resistance testing. Ask whether the lab can also check for macrolide resistance, since that guides the choice of medicine.
A follow-up plan. A good visit includes what to do if symptoms continue.
A partner plan. A good visit includes advice on telling partners and when to be seen.

Where to ask about testing in Los Angeles

Here is a point that is easy to miss. None of the clinic pages we reviewed say whether a given site runs a mycoplasma genitalium test. Clinics list chlamydia, gonorrhea, syphilis and HIV testing much more often. So the practical step is to call and ask. You can say you are asking about mycoplasma genitalium testing, and whether resistance testing is available.

The Los Angeles County Department of Public Health (DPH) runs sexual health clinics. Its Sexual Health Clinics page says patients pay nothing, and that insurance is billed if the patient has it, with no copay or coinsurance. These are some options in the city:

Central Health Center, 241 Figueroa St., Los Angeles, CA 90012. DPH lists STD testing, HIV testing, PrEP, PEP, doxy-PEP and treatment. Appointments are preferred, and walk-ins are limited.
MLK Jr. Center for Public Health, 11833 S. Wilmington Ave, Los Angeles, CA 90059. DPH lists the same set of services. Appointments are preferred, and walk-ins are limited.
Pacoima Health Center, 13300 Van Nuys Blvd, Pacoima, CA 91331. DPH describes this site as screening only. People with symptoms or a possible exposure are directed to book at another DPH clinic for evaluation and treatment.

All DPH sexual health appointments go through one scheduling line, (213) 449-7009. DPH says results come through the LA Health Portal in 2 to 10 business days. DPH also says its clinics are open to everyone regardless of citizenship and that it does not report immigration status.

Other community options include the Los Angeles LGBT Center’s McDonald/Wright Building at 1625 N. Schrader Blvd., which the county lists as accepting walk-ins Monday to Friday, 10am to 7pm. APLA Health’s Out Here Sexual Health Center is at 3741 S. La Brea Ave., and APLA says its Out Here locations offer free or low-cost sexual health services. Neither organization’s page states whether it tests for mycoplasma genitalium, and prices for STI testing are not listed on the pages we reviewed, so check with the clinic first.

For a fuller list with addresses, see the local testing list. Our guide to STD testing in Los Angeles covers how the visits work. You can also search the CDC’s directory at gettested.cdc.gov, which lists testing sites by ZIP code.

Teens and young adults

California Family Code section 6926 allows a minor aged 12 or older to consent to STI testing and treatment. LA County DPH tells patients 12 and older that they can be tested and treated without their parents knowing, and parents are not liable for payment for that care. Children’s Hospital Los Angeles lists STD services for ages 12 to 24 at 3250 Wilshire Blvd., 3rd Floor, phone (323) 361-7550. The county’s listing does not state costs or whether it tests for mycoplasma genitalium.

Local context

The Los Angeles County Department of Public Health reported 493 chlamydia cases per 100,000 people in its 2024 STI Surveillance Snapshot (provisional, and excluding Long Beach and Pasadena). Gonorrhea was 252 per 100,000. The county does not publish a comparable figure for mycoplasma genitalium in the materials we reviewed, because it is not a routinely reported condition. Chlamydia and gonorrhea are the most common causes of urethritis and cervicitis, which is why clinicians usually check for them first.

A short checklist for your visit

Write down your symptoms, when they started, and any treatment you have already had.
Ask whether the clinic can test for mycoplasma genitalium, and whether resistance testing is included.
Ask what happens next if the result is negative and symptoms continue.
Ask how to reach partners and whether they should be seen.
Ask when and how you will get results.

Being tested for an STI is a routine part of health care. You do not need a reason beyond wanting to know.

Mycoplasma Genitalium: What It Is and Where to Get Tested in Los Angeles