Trichomonas Test

This is a test used to diagnose an infection with Trichomonas vaginalis. This is a sexually transmitted, microscopic parasite that causes vaginal infections in women and urethritis in some men. This test is often done if there is vaginal discharge or pain on urination. If you have an infection with another sexually transmitted disease, your caregiver might test for trichomonas as well. Secretions or a sample are collected on a swab and are examined under a microscope or cultured to detect the presence of Trichomonas vaginalis.

Trichomonas is one of the most common sexually transmitted diseases. An infected person is at greater risk of getting other sexually transmitted diseases, so your caregiver may want to test for these other infections also.

Trichomonas infection can affect pregnancy, contributing to premature birth and low birth weight. You should inform your physician if you may be pregnant. The doctor may medically manage a woman who is infected and in her first three months of pregnancy differently.


In women, a swab of secretions is collected from the vagina. In men, a swab is inserted into the urethra.


A positive test indicates an active infection that requires treatment with antibiotics. It is usually treated with an antibiotic called metronidazole. All current sexual partners must be treated at the same time or the patient is likely to become re-infected.

The Center for Disease Control (CDC) recommends the following guidelines to avoid infection or reinfection:

  • Abstain from sexual intercourse

  • Use a latex condom properly, every time you have sexual intercourse, with every partner.

  • Limit your sexual partners. The more sex partners you have, the greater your risk of encountering someone who has this or other STI's.

  • If you are infected, your sexual partner(s) should be treated. This will prevent you from getting reinfected.


It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.