Trichomoniasis

Trichomoniasis is a sexually transmitted infection (STI) caused by the parasite Trichomonas vaginalis.

Key points

  1. Trichomoniasis is common and easy to treat with antibiotics.
  2. Some people with trichomoniasis don’t notice symptoms.
  3. Women need a swab from your vagina to diagnose trichomoniasis. It is difficult to test for in men, so men are usually just treated if you have had sex with someone with the infection.
  4. If you have trichomoniasis, you need to tell anyone you have had sex with in the past 3 months to get tested and treated for trichomoniasis.
  5. Avoid sex for 7 days after you and your partner(s) have been treated so you don’t pass the infection on, or use condoms if this is not possible.

What are the causes of trichomoniasis?

Trichomoniasis is caused by a parasite called Trichomonas vaginalis. Trichomoniasis is transmitted through contact with genital fluids from the penis or vagina of someone who has the infection. Ιt can also be passed on by sharing sex toys, eg, vibrators. You don’t need to have many sexual partners to get the infection.

What are the symptoms of trichomoniasis?

About 70% of infected people don’t have any signs or symptoms. When trichomoniasis does cause symptoms, they can range from mild irritation to severe inflammation. Some people get symptoms within 5–28 days of being infected, but others don’t develop symptoms until much later. Symptoms can come and go.

Women

  • You may feel pain, burning or itching in your genital area.
  • You may also feel pain or discomfort when passing urine (peeing) or having sex.
  • You may notice a discharge or fluid leaking from your vagina.
  • You may also have a bad odour (smell) in your genital area.
  • Many women have no symptoms.

Men

  • Μost men don’t have symptoms.
  • However, you can still pass trichomoniasis on.
  • You may have discharge or fluid leaking from your penis.
  • You may also have pain when passing urine (peeing) or during ejaculation (coming).
  • You may have pain, swelling or redness around the head of your penis.

How is trichomoniasis diagnosed? 

As the symptoms of trichomoniasis are similar to other STIs, it can be difficult to diagnose. Your doctor will ask you a few questions about your symptoms, and whether you have had any sexual contact with someone with trichomoniasis infection. Your doctor will also examine your genital area.

For women, a swab will be taken from your vagina. For men, it is more difficult to test. However, depending on whether you have symptoms, your doctor may suggest a urine test or a swab. Sometimes, your doctor may offer treatment straight away without doing a test if you have had sex with someone who has trichomoniasis.

If you have trichomoniasis, your doctor may also test for other STIs or do a sexual health check.

How is trichomoniasis treated?

In most cases a single dose of the correct antibiotic reliably and rapidly cures trichomoniasis. The antibiotic is called metronidazole. The tablets sometimes make you feel a bit sick, but it helps if you take them with food. Don’t drink alcohol for 24 hours after taking the tablets as it will make you feel really sick.

Without treatment, the infection can last for months or even years.

About 1 in 5 people get infected again within 3 months after treatment. To avoid getting reinfected, make sure all your sex partners get treated too, and don’t have sex again or use condoms if this is not possible until all your symptoms go away (about a week). Get checked again if your symptoms come back.

What are the complications of trichomoniasis?

Trichomoniasis can cause complications if it is untreated.

  • It can increase the risk of getting or spreading other STIs, such as HIV and bacterial vaginosis. For example, trichomoniasis can cause genital inflammation, which makes it easier to get infected with the HIV virus, or to pass the HIV virus on to a sex partner.
  • Both men and women are at increased risk of infertility.
  • Trichomoniasis can cause pelvic inflammatory disease in women.
  • Pregnant women with trichomoniasis are more likely to have your baby too early (preterm), and for your baby to have a low birth weight.

How can I prevent trichomoniasis?

Practicing safer sex can protect you from getting, or passing on trichomoniasis and other STIs. The following tips can help prevent STIs:

  • Use condoms during vaginal, oral or anal sex with every partner, every time.
  • Keep sex toys clean and avoid sharing sex toys with others.
  • Have sex with only one partner if possible.
  • Avoid having sex if you or your partner has any symptoms such as sores, ulcers, discharge or any pain around the genital area – get checked by a doctor first.
  • Have regular STI checks (every 3 months), especially if you have had any unprotected sex (sex without a condom) or have more than one partner.
  • Wash your hands with soap and water before and after sex or sexual play.

Read more about safer sex.

What support is available with trichomoniasis?

If you think you have trichomoniasis or any other sexual health concerns, you can see or talk to your GP. Alternatively, there are other options where you can get help.

Sexual health clinics
Family Planning clinics

Learn more

Trichomoniasis patient information New Zealand Sexual Health Society
Trichomoniasis Family Planning, NZ
Trichomoniasis (Trich) Just The Facts, NZ
Trichomoniasis NHS, UK

References

  1. Trichomoniasis management summary New Zealand Sexual Health Society, 2017
  2. Trichomoniasis patient informationNew Zealand Sexual Health Society
  3. Trichomoniasis Family Planning, NZ
  4. Trichomoniasis (Trich) Just The Facts, NZ
  5. Trichomoniasis infection HealthInfo Canterbury, NZ
  6. Trichomoniasis Patient Info, UK
  7. Trichomoniasis  CDC Fact Sheet
Credits: Health Navigator Editorial Team.