Trichomoniasis - American Sexual Health Association


Trichomoniasis (also called trich) is a common, curable sexually transmitted infection (STI) caused by a parasitic protozoa called Trichomonas vaginalis. More than one million new cases occur each year in the U.S.

Trichomoniasis may cause symptoms in women, but most men do not have symptoms. You may need to talk to your healthcare provider about whether or not you should be tested. If you have trichomoniasis, you are more likely to contract HIV if you are exposed–so getting tested and treated is important.


How does someone get trich?
Trich is spread through sexual contact with an infected partner: this includes penis-to-vagina intercourse or genital-to-genital contact.

What are the symptoms of trich?
Only about 30 percent of people that have trichomoniasis develop any symptoms. When trich does cause symptoms, they can range from mild irritation to severe inflammation.

Symptoms of trichomoniasis are more common in women. These include:

  • Vaginal discharge that is green, yellow or grey
  • A bad vaginal smell
  • Itching in or around the vagina
  • Pain during sex
  • Pain when urinating

Most men don’t have symptoms of trich but when they do, symptoms can include itching or irritation inside the penis, a discharge or pain when urinating.

Some people with symptoms of trich get them within 5 to 28 days after being infected, but others do not develop symptoms until much later. Symptoms can come and go, and without treatment, the infection can last for months or even years.

How can trich be prevented?
Using latex condoms correctly every time during sexual intercourse will help reduce the risk of getting or spreading trichomoniasis.

How is trich diagnosed?
It is not possible to diagnose trichomoniasis based on symptoms alone (remember–many people don’t have symptoms). A healthcare provider must perform a test to diagnose trich.

The parasite is harder to detect in men than in women. General tips for women to help their provider find out what they may have include:

Schedule the exam when you’re not having your monthly period.
Don’t douche 24 hours before your exam.
Don’t use vaginal sprays 24 hours before your exam.
If you have sex less than 24 hours before the exam, use condoms.

Healthcare providers often diagnose trich in women by putting a sample of vaginal fluid or discharge on a slide (called a “wet preparation”) and viewing the parasite under a microscope. This test is not always reliable.

A culture test is another method to detect trich, and can be used with males and females. Culture tests use urine, or a swab from the vagina or urethra, and make the trich parasite easier to find by “growing” it in a lab.

Recently, tests that are much more accurate have become available, including DNA tests that are reliable in men and women. These tests can be done with vaginal swabs or urine. Women may have a trich test done along with a pelvic exam. One of these tests even allows healthcare providers to check for trichomoniasis, chlamydia, and gonorrhea using the same sample.

How is trich treated?
Trichomoniasis is curable with antibiotics, typically metronidazole (Flagyl) or Tinidazole (Tindamax). If you are being treated for trichomoniosis, keep these facts in mind:

Use all the medicine prescribed, even if your symptoms go away
Sex partners must also be treated, or you will get trich again
Do not have sex until all partners have finished the medication

What if I have trich while pregnant?
Trichomoniasis can cause babies to be born early or with low birth weight (less than 5.5 pounds). If you think you may be pregnant – or are planning to become pregnant-be sure to talk to your healthcare provider and ask about testing for trich. Women in the first three months of pregnancy should not take medicine for trich because it might hurt the baby. You can take medicine after the first three months.

Are there other complications with trich?
Trich can cause genital inflammation that makes it easier to become infected with the HIV virus or to pass the HIV virus on to a sex partner.

ASHA Survey Shows Most Women Unaware of Trich

Even though trich is the most common curable sexually transmitted Infection (STI), a new survey conducted by ASHA in January-February 2013 shows that only one in five (22%) women are familiar with it.

As illustrated below, women surveyed perceive trich as the least common STI, when in reality there are more total (new and existing) cases of trich in the U.S. (estimated 3.7 million) as there are syphilis, chlamydia and gonorrhea combined.

Trichomoniasis survey results

Click on image to enlarge

The CDC recommends that any sexually active woman seeking treatment for vaginal discharge should be tested for trich. However, 65% of women surveyed would not seek medical attention if they experienced unusual symptoms, instead waiting to see if the symptoms go away or treating themselves with over-the-counter medicine.

Pregnant women with trich are more likely to have preterm or low birth weight (less than 5.5 pounds) babies. Trich also increases the risk of acquiring and transmitting HIV, the virus that causes AIDS. Among women surveyed who were concerned about contracting an STD, nearly half (49%) worry about trich increasing their risk of HIV.

ASHA recommends that women encourage their partners to get tested, as 1 in 5 people can be reinfected within three months of treatment. According to the survey, 63% of women cite having only one sex partner as a reason they would not get tested for trich. Yet a woman can be at risk for trich even if she only has one sexual partner.

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