Mycoplasma and Ureaplasma are types of bacteria that are unique because they don’t have a cell wall. This lack of a cell wall makes them very transmissible and resistant to all but three types of antibiotics. They exist in any mucus-prone areas, like the throat, nose, or genitalia. In fact, this bacterium exists naturally in the genital tract, but four different strains could cause infection:

• Mycoplasma genitalium (M. genitalium)
• Mycoplasma hominis (M. hominis)
• Ureaplasma parvum
• Ureaplasma urealyticum (U. urealyticum)

Mycoplasma is also sexually transmitted, often causing symptoms similar to gonorrhea and chlamydia. However, symptoms and infection depend on the specific strain and the area in which a person lives. Not all countries have the same prevalence of each strain, and some strains are more resistant to antibiotics than others. Therefore, some countries may not be able to treat the infection as effectively due to antibiotic resistance.

The presence of mycoplasma in urological issues appears to be higher in men. However, this may be because women are often asymptomatic:

• General symptoms in men include painful urination (dysuria), urgency, an itchy urethral opening, and abnormal discharge.
• M. urealyticum and M. genitalium can cause urethritis (mostly) in men, even when gonorrhea is not present.
  • M. genitalium is the second-most common cause of urethritis after chlamydia.
• M. genitalium is associated with rectal infections in 1 – 26% of men who have sex with men (and 3% of women who have anal sex).

Despite being mostly asymptomatic in women, these bacteria can cause a wider range of infections and symptoms in women:

• Women's symptoms can include bladder issues and pelvic inflammatory disorder (PID).
  • PID is caused by any infection in the reproductive organs.
• M. genitalium may cause endocervicitis.
  • This causes abnormal discharge, mid-cycle spotting, and a tender cervix.
• M. hominis is associated with bacterial vaginosis (BV), which is a vaginal infection often caused by an imbalance of the normal bacteria in the vagina. Sexual activity or poor hygiene can increase the risk of BV, but it is not considered a sexually transmitted infection (STI).
  • M. hominis and U. urealyticum may cause urethritis in women, but not much research has been done to confirm this.
  • High levels of M. hominis in the vagina may be related to HIV shedding, meaning it is highly transmissible at that moment.

Resistance to antibiotics continues to pose a problem for healthcare providers.  Fortunately, Mycoplasma and Ureaplasma often do not cause symptoms and may not require treatment. However, if they are found in a urine sample, a healthcare professional may explore any infection and treat it properly.

Key Takeaways

• Mycoplasma and Ureaplasma are sexually transmitted, highly antibiotic-resistant bacteria that are prominent on most continents.
• Depending on the strain, patients may be asymptomatic or experience pain or discomfort.
• Mycoplasmas are easily transmissible and hard to treat, posing an added challenge for health care professionals.
• If bladder or pelvic issues are bothersome, it may help to speak with a sexual health professional.

Resources

• Ardizzone, C. M., & Jordan, S. J. (2026). Guidelines and diagnostic assays for mycoplasma Genitalium. Open Forum Infectious Diseases, 13(Supplement_2), S1360–S1366. https://doi.org/10.1093/ofid/ofag003
• Combaz-Söhnchen, N., & Kuhn, A. (2017). A systematic review of Mycoplasma and ureaplasma in Urogynaecology. Geburtshilfe Und Frauenheilkunde, 77(12), 1299–1303. https://doi.org/10.1055/s-0043-119687
• Lanao AE, Chakraborty RK, Cristovao D, et al. Mycoplasma Infections. [Updated 2023 Aug 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK536927/
• Ramaloko, W. T., Maningi, N. E., & Osei Sekyere, J. (2025). Global prevalence, resistance rates, and underlying resistance mechanisms of clinical mycoplasma and ureaplasma species. Journal of Applied Microbiology, 136(1). https://doi.org/10.1093/jambio/lxae308
• White, E. (2023, July 10). Genital mycoplasmas | Diagnosis & Disease Information. Infectious Disease Advisor. https://www.infectiousdiseaseadvisor.com/ddi/genital-mycoplasmas/