What is trichomoniasis?

Trichomoniasis, also called "trich," is a common sexually transmitted infection (STI) that affects people of all genders. It is caused by a protozoan parasite called Trichomonas vaginalis and is a cause of vaginal infections and urethral infections in people with penises. 

Is it common?

Trichomoniasis is an STI that affects approximately 5 million people in the US every year and is one of the most common, curable causes of vaginal infections.

How is it transmitted?

As with other STIs, trichomoniasis is spread through sexual contact. Transmission can occur even if a person does not have symptoms of infection. People with vulvas contract trichomoniasis from infected partners with vulvas or penises while people with penises usually contract it only from partners with vulvas. Using condoms and/or dental dams provide some protection. Their use is strongly encouraged, but is not 100% safe. Trichomoniasis can also survive on infected objects like sheets, towels, and underwear and could be transmitted by sharing them.

What are the symptoms?

Many people with trichomoniasis experience no symptoms; however, some common symptoms women may experience include:

  • Genital itching and/or burning

  • Vaginal or vulval redness

  • Frothy yellow-green vaginal discharge with a strong odor

  • Blood spotting

  • Frequent and/or painful urination

  • Discomfort during intercourse

  • Abdominal pain

People who menstruate might also find that the above symptoms worsen after menstruation and that the symptoms may be confused with a yeast infection. This fact emphasizes the importance of always having a yeast infection diagnosed properly, because it might not be a yeast infection.

People with penises are usually asymptomatic, but if they have symptoms, these can include:

  • Unusual penile discharge

  • Painful urination

  • Burning sensation after ejaculation

  • Tingling inside the penis.

How soon after exposure to trichomoniasis will symptoms appear?

If symptoms appear, it usually takes from 3 to 28 days for them to develop. 

How is it diagnosed?

A medical provider will take a swab of fluid from the vagina or the urethral opening of the penis and will examine it under a microscope to see if trichomoniasis is present.

How is it treated?

Trichomoniasis can be treated with oral antibiotics, usually a single dose. It is especially important that both partners are treated at the same time because an infected partner, even if they have never had symptoms or if their symptoms have stopped, can continue to infect a partner until they have been treated. Anyone being treated for trichomoniasis should avoid sex until they and their partner(s) have completed the treatment.

Can trichomoniasis infections be dangerous?

As mentioned above, trichomoniasis is one of the most common and most curable STIs. The symptoms are more annoying than they are threatening to your health. The genital inflammation caused by trichomoniasis might however, increase a person's risk of acquiring HIV infection if s/he is exposed to HIV or might also increase the chances of transmitting HIV infection to a sex partner. In rare cases, trichomoniasis in pregnant women may cause a premature rupture of the membranes and early delivery. 

Related Links

For more information about trichomoniasis, you can visit:

Centers for Disease Control

  • 401.863-2794
    Health Promotion
  • 401.863-3953
    Health Services
  • 401.863-6000
    Sexual Assault Response Line
  • 401.863-4111
  • 401.863-3476
    Counseling & Psychological Services
  • 401.863-4111