Mycoplasma genitalium: the STI a standard panel does not measure

Yes, mycoplasma genitalium is an STI. The 2021 European guideline describes the bacterium as an established cause of urethritis, and of inflammation higher up in women (Jensen, 2022). And still it is not part of a standard Dutch STI panel, ours included.

That is an odd combination, and it creates a lot of confusion.

What we see in practice is this: someone has symptoms, gets checked for chlamydia and gonorrhoea, receives a clean result, and keeps the symptoms. Only much later does the name mycoplasma come up. Below you will read why it runs that way.

Is mycoplasma an STI?

Yes. Mycoplasma genitalium is passed on through sexual contact and can cause urethritis. In women the bacterium is also linked to inflammation of the cervix. The European guideline treats it as a full cause, with its own testing policy and its own treatment advice (Jensen, 2022).

Which mycoplasma you mean does matter though.

The name mycoplasma covers several bacteria, and their status differs sharply. Mycoplasma genitalium counts as an STI. Mycoplasma hominis and ureaplasma do not, or at least far less clearly. Test pages regularly blur that line, and that is exactly what gives people an unnecessary fright.

What symptoms does mycoplasma genitalium cause?

The symptoms resemble chlamydia. In men it is usually a burning feeling when urinating and sometimes discharge from the urethra. In women there can be discharge, bleeding between periods, or lower abdominal pain. A sizeable share of people notice nothing.

One pattern does stand out.

Mycoplasma genitalium tends to surface with symptoms that linger. Research into non-gonococcal urethritis shows two things. Several causes are often involved at once. And in a share of men, no known cause is found at all (Jordan, 2020). Persistent symptoms after a negative standard test are therefore not a strange story, but a familiar scenario.

What else your symptoms could mean is covered in our article on urethritis.

Why is mycoplasma not in a standard STI panel?

Put simply: because untargeted testing can do more harm than good here. The bacterium is hard to treat and resistance to the usual antibiotics is rising. Testing everyone without symptoms then produces many positive results that get treated, and that is exactly what drives resistance further up.

That is an awkward argument for a testing provider.

We earn money from tests. Even so, this is why mycoplasma genitalium is not in our panel, and we think writing that down is fairer than quietly selling the test alongside. The European guideline takes the same line: testing is tied to symptoms, and treatment is matched to resistance testing (Jensen, 2022).

The Dutch GP standard on the STI consultation likewise keeps a restrained testing policy for this bacterium in primary care. The RIVM tracks national STI figures and does not report mycoplasma genitalium as part of routine STI surveillance.

When is mycoplasma actually tested for?

In practice a targeted test comes into view with persistent symptoms that fit urethritis, after chlamydia and gonorrhoea have been ruled out. That is not a self-test decision. A doctor weighs how long symptoms have lasted, what has already been treated, and whether a partner is involved.

So the order is: rule out the common things first.

You can do that part with us through a test for chlamydia, gonorrhoea and trichomonas. If symptoms persist after that, the GP or a sexual health clinic is the next step, not another online test.

What does a positive mycoplasma result mean?

It means the bacterium has been detected. Whether treatment is needed depends on your symptoms and on resistance testing. The European guideline advises letting the choice of antibiotic follow the mutations found, rather than giving the same drug by default (Jensen, 2022).

A positive result without symptoms is a harder story.

Picture two men aged 25 getting exactly the same positive result. One has had trouble urinating for 3 weeks. The other tested without any symptoms at all, just to be sure.

For the first, that result is a lead. For the second it is mostly a number without a story, and that distinction is what we've found missing on most test pages.

For the related bacteria ureaplasma and Mycoplasma hominis, the European STI Guidelines Editorial Board published a 2018 position statement advising against routine testing in people without symptoms (Horner, 2018). The same logic makes a symptom-free positive hard to interpret for mycoplasma genitalium too.

Discuss a result like that with a doctor before starting a course. What treatment looks like, and why it fails more often than you would expect, is covered in mycoplasma genitalium treatment.

Further reading

For the wider picture of urethral symptoms: urethritis. For the related bacteria that are not STIs: ureaplasma urealyticum and mycoplasma hominis.

And if you mainly want to know which test you need when: which test you need when.

References

• Jensen JS, et al. 2021 European guideline on the management of Mycoplasma genitalium infections. Journal of the European Academy of Dermatology and Venereology, 2022. PMID 35182080.
• Jordan SJ, et al. Aetiology and prevalence of mixed-infections and mono-infections in non-gonococcal urethritis in men: a case-control study. Sexually Transmitted Infections, 2020. PMID 31515293.
• Horner P, et al. Should we be testing for urogenital Mycoplasma hominis, Ureaplasma parvum and Ureaplasma urealyticum in men and women? A position statement from the European STI Guidelines Editorial Board. Journal of the European Academy of Dermatology and Venereology, 2018. PMID 29924422.
• NHG-Standaard Het soa-consult, Dutch College of General Practitioners. Accessed July 2026.
• RIVM, Sexually transmitted infections in the Netherlands, annual report. Accessed July 2026.
• Thuisarts.nl, Pain when urinating. Accessed July 2026.

Every test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.