Test Quick Guide

Trichomoniasis is a sexually transmitted disease (STD) caused by an infection with the parasite Trichomonas vaginalis. This parasite is spread from person to person during sex, most often through penis-to-vagina or vulva-to-vulva contact. It is uncommon for this infection to affect another part of the body such as the mouth, hands, or anus.

Trichomoniasis testing detects the Trichomonas vaginalis parasite in a sample of urine or body fluid taken from your genitals. A health care provider may order trichomoniasis testing when someone complains of symptoms, is at an increased risk of this infection, or has recently finished treatment for this common STD.

About the Test

Purpose of the test

The purpose of a trichomoniasis test is to find an infection with the parasite Trichomonas vaginalis. Trichomoniasis testing may be used for screening, diagnosis, or monitoring:

  • Diagnostic testing describes determining the cause of your symptoms. The majority of people with this infection don’t develop symptoms, but approximately 30% will have symptoms similar to those caused by other STDs.
  • Screening for trichomoniasis looks for an infection in patients without symptoms. This is recommended for women and anyone with a vagina at an increased risk of infection.
  • Monitoring tests are used after you finish treatment for trichomoniasis. Because a significant number of patients are reinfected by an untreated partner, checking again for trichomoniasis several months after treatment ends is an important follow-up test.

What does the test measure?

Trichomoniasis testing looks for evidence of the parasite Trichomonas vaginalis.

Several laboratory tests may be used to detect trichomoniasis. The test method selected for an individual depends on their anatomy and test availability.

  • Wet-mount microscopy is the most common method of diagnosing trichomoniasis in women and anyone with a vagina. During this test, the patient’s doctor examines a sample of vaginal fluid under a microscope and looks for the Trichomonas vaginalis parasite. This testing method is quick and practical, allowing doctors to detect the parasite during your appointment and prescribe treatment immediately.
  • Nucleic acid amplification testing (NAAT) is considered the gold standard for detecting a trichomoniasis infection and can be used in people of all genders. This test can identify the genetic material of the parasite, called DNA or RNA, in a sample of urine or a swab of fluid from the vagina or cervix. While more time-consuming than wet-mount microscopy, NAAT is better at detecting this infection.
  • Cultures allow health professionals to grow and detect the parasite in a laboratory. This test, still commonly performed if NAAT test results are negative, can accurately detect trichomoniasis, but results take three to seven days. In patients whose infections are resistant to common treatments, cultures may also be used to try various treatments in the lab and see which is the most effective, which is known as drug susceptibility testing.
  • Rapid antigen testing is a quick method of detecting Trichomonas vaginalis antigens in vaginal fluid. Antigens are substances that cause your immune system to react against the parasite. This test can be performed in a doctor’s office and results are available in 10 to 15 minutes.

When should I get a trichomoniasis test?

To help decide if trichomoniasis testing is appropriate, a doctor starts by discussing your symptoms and performing a physical exam as well as a pelvic exam in patients with a vagina. Doctors recommend testing for trichomoniasis when you are at a high risk of contracting this infection, have symptoms suggestive of infection, or have completed the prescribed treatment.

Diagnosing trichomoniasis in patients with symptoms of this infection relies on one of several test methods that can detect Trichomonas vaginalis. When symptoms occur, they often begin around five to 28 days after infection. The frequency and type of symptoms you may experience depends on your anatomy.

For those with a penis, symptoms appear in less than 25% of patients. Symptoms of trichomoniasis in this group include:

  • Discharge from the urethra
  • Burning after ejaculating or urinating
  • Irritation in the penis
  • Testicular pain
  • Cloudy urine

For those with a vagina, only a small portion experience symptoms soon after infection. Symptoms may become more common over time and get worse during menstruation. When they occur, symptoms of this infection can include:

  • Abnormal discharge from the vagina
  • Discomfort during and after urinating
  • Irritation and redness in the vagina
  • Bleeding after sex

Patients being tested for trichomoniasis may receive other STD tests at the same time, including chlamydia and gonorrhea tests.

Diagnostic testing may also be performed in some women and people with a vagina if signs of trichomoniasis are detected during a routine Pap smear. If a Pap smear indicates a possible asymptomatic infection, a doctor may recommend wet-mount microscopy and a NAAT, culture, or rapid test to confirm a diagnosis of trichomoniasis.

Screening for trichomoniasis is recommended for several groups who are at an increased risk of acquiring this STD. How often to get tested depends on the patient’s specific circumstances. For men and anyone with a penis, screening is not recommended. It is often recommended for sexually active women and anyone with a vagina if:

  • You have been diagnosed with HIV
  • You live or receive care in an area where this infection is common, including correctional facilities
  • You have new or multiple sex partners
  • You have a history of STDs

Monitoring patients after treatment for trichomoniasis helps to ensure that patients don’t become reinfected by an untreated partner after finishing therapy. In women and anyone with a vagina, some will become reinfected, and repeat testing for trichomoniasis is recommended within three months of completing treatment, or sooner if symptoms return.

Because the frequency and timing of trichomoniasis testing depends on several factors, it’s important to discuss recommendations for testing with your doctors.

Finding a Trichomoniasis Test

How can I get a trichomoniasis test?

Testing for trichomoniasis can be performed in a variety of settings, including hospitals, doctors’ offices, and community health clinics. You can order a trichomoniasis test online with testing at a local lab.

Trichomoniasis testing can be ordered by a doctor or other health care provider. Before screening patients who aren’t experiencing symptoms, a health care provider can determine the risk of acquiring trichomoniasis and recommend a schedule for regular testing if necessary.

If you are experiencing symptoms of trichomoniasis, the health care professional will order the most appropriate test to rule out or confirm trichomoniasis as the cause of symptoms.

Can I take the test at home?

At-home trichomoniasis tests are available to detect this common STD at home. Using a self-collection test kit, you can obtain a sample at home and send it to a laboratory for analysis.

At-home trichomoniasis tests use either NAAT or nucleic acid probe technology to find evidence of infection with Trichomonas vaginalis in a sample of urine or a swab collected from the vagina.

Regardless of the results of at-home trichomoniasis testing, you need to follow up with your doctor for confirmation and a discussion of the test results.

How much does the test cost?

The cost of trichomoniasis testing depends on many factors including who orders the test and where it is conducted.

When trichomoniasis testing is ordered by a health professional, the cost of testing may be paid for by your health insurance. Even with health insurance, though, there may be some patient expenses such as copays and deductibles.

If you don’t have health insurance, the cost of trichomoniasis testing may be paid out of pocket. Testing costs may include an exam fee, technician fees, and the cost of the trichomoniasis test itself.

If you’re concerned about the cost of testing for trichomoniasis, contact your local health department or a community-based organization that provides free or low-cost STD testing.

Taking a Trichomoniasis Test

Trichomoniasis testing may be performed using a sample of urine or body fluid taken from the genitals using a swab or small brush. Samples used for testing can be collected by a medical professional or by you as the patient.

Before the test

There are no special precautions to take before a trichomoniasis test. If you are taking the test from home, be sure to follow all instructions carefully. Before collecting a sample for a trichomoniasis test, a health care provider may perform a physical exam that includes looking at your genitals for signs of trichomoniasis.

During the test

The first step in testing for trichomoniasis usually involves collecting a sample and performing wet-mount microscopy. Samples may be taken from the penis or vagina with a small brush or swab. After preparing the samples, a doctor examines them under a microscope for the parasite Trichomonas vaginalis. The collection process may be uncomfortable, but the discomfort is typically very brief.

If you are asked to provide a urine sample, you may be instructed on providing a clean catch sample. You may be given a cleansing pad to clean your genitals and a container to collect your sample. After using the cleansing pad, you start urinating into the toilet before moving the collection container under your urine stream. Once you’ve collected sufficient urine, you finish urinating in the toilet and then return the collection container to your health care provider.

After the test

There are no risks or side effects of trichomoniasis testing. You can return to normal activities after the test is complete.

Trichomoniasis Test Results

Receiving test results

Trichomoniasis test results may be available within a few minutes or up to several days after testing depending on the type of test being conducted. Results of a culture usually take additional time to allow the parasite to be grown in the laboratory.

Your doctor may discuss your test results over the phone or in a follow-up appointment. Test results may also be available through an electronic medical record or an online health portal.

Interpreting test results

Trichomoniasis test results are typically reported as positive or negative. Results reflect whether evidence of the parasite Trichomonas vaginalis was detected in the test sample. Cultures can correctly detect an active infection in 70 to 85% of patients with trichomoniasis, although this can vary based on the type of test sample being evaluated.

A positive result indicates that you likely have trichomoniasis. After diagnosis, your doctor may also suggest other STD tests, including tests for HIV, syphilis, gonorrhea, and chlamydia. If an infection is found, your sexual partner(s) should also be tested and treated.

If you’re diagnosed with trichomoniasis, it’s important to refrain from having sex until you and your sex partners have completed treatment. This usually takes around seven days. Follow-up trichomoniasis testing is recommended to ensure that you aren’t reinfected with this parasite and is typically conducted two weeks to three months after you finish treatment.

If your initial test is with wet-mount microscopy and is negative, further testing is still often necessary. To confirm a negative test result, samples collected from the penis or vagina may be used for NAAT or other methods of trichomoniasis testing.

Many people find it helpful to ask their doctor specific questions about their test results. Questions you may find helpful to discuss with your doctor include:

  • What type of test was used?
  • What is my trichomoniasis test result?
  • Based on my test results, are any follow-up tests necessary?
  • What should I tell my sex partners about my test result?
  • How often should I be tested for trichomoniasis and other STDs?

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