Trichomoniasis, also called trich is a sexually transmitted infection caused by a parasite. It is among the most common sexually transmitted infections. Risk factors include multiple sexual partners and not using condoms during sex.

What is it?

  • In Australia, Trichomoniasis is more common in older women and women from regional and remote areas, especially Aboriginal & Torres Strait Islander women
  • Uncommon cause of vaginal discharge or male urethritis in urban settings
  • Long natural history (years) if not treated in women
  • Without treatment, the infection is cleared more quickly in men than women

Signs and Symptoms

Usually asymptomatic Malodourous vaginal discharge - a frothy or smelly discharge from the vagina that is yellow grey or green
Urethral discharge (uncommon) Valval itch/soreness
Dysuria (uncommon) Pain low in the tummy, pain during sex or when urinating


  • Your GP is likely to take a sample from inside the vagina to test for Trichomoniasis
  • Men can be checked with a urine test or a swab from the opening of the penis


Trichomoniasis is treated with antibiotics. Most people only need a single large does, but some may need longer as it often comes back. If you have Trichomoniasis, any current sexual partner should be tested too, even if they do not have any symptoms.

If your symptoms do not go away after treatment, you need to talk to your GP or sexual health worker.

Without treatment, Trichomoniasis can last months or even years. It can cause premature labour, low birth weight or increase your risk of getting HIV.

Recommended follow-up

  • Not required if symptoms resolve
  • Consider testing for other STI's at three-month visit, if not undertaken at first presentation or retesting post window period
  • Re-testing is recommended for patients who remain symptomatic or where partner treatment remains uncertain which should be performed after 4 weeks (this also provides the opportunity to re-test, post window period for other STI's

Contact tracing

  • For all sexual partners
  • There is currently insufficient data to provide a definitive period for this, partner treatment encouraged presumptively

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