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Trichomoniasis (TRIK-uh-muh-NEYE-uh-suhss) or "trich" is a sexually transmitted infection (STI) caused by a parasite. The parasite is spread most often through vaginal, oral, or anal sex. It is one of the most common STIs in the United States and affects more women than men. It is treated easily with antibiotics, but many women do not have symptoms. If left untreated, trichomoniasis can raise your risk of getting HIV.

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What is trichomoniasis?

Trichomoniasis is an STI caused by a parasite. It is one of the most common STIs in the United States.1

Who gets trichomoniasis?

Trichomoniasis is more common in women than men. It affects more than 2 million women ages 14 to 49 in the United States.2

Trichomoniasis affects more African-American women than white and Hispanic women. The risk for African-American women goes up with age and lifetime number of sex partners.2

How do you get trichomoniasis?

Trichomoniasis is spread through:

  • Vaginal, oral, or anal sex. Trichomoniasis can be spread even if there are no symptoms. This means you can get trichomoniasis from someone who has no signs or symptoms.
  • Genital touching. A man does not need to ejaculate (come) for trichomoniasis to spread. Trichomoniasis can also be passed between women who have sex with women.

What are the signs and symptoms of trichomoniasis?

Most infected women have no signs or symptoms. If you do get signs or symptoms, they might appear five to 28 days after exposure and can include:

  • Irritation and itching in the genital area
  • Thin or frothy discharge with an unusual foul odor that can be clear, white, yellowish, or greenish
  • Discomfort during sex and when urinating
  • Lower abdominal pain (this is rare)

If you think you may have trichomoniasis, you and your sex partner(s) need to see a doctor or nurse as soon as possible.

How is trichomoniasis diagnosed?

To find out whether you have trichomoniasis, your doctor or nurse may:

  • Do a pelvic exam
  • Use a cotton swab to take a fluid sample from your vagina to look for the parasite under a microscope
  • Do a lab test, such as a DNA test or a fluid culture. A culture tests uses urine or a swab from your vagina. The parasite then grows in a lab. It takes up to a week for the parasite to grow enough to be seen.

A Pap test is not used to detect trichomoniasis.

If you have trichomoniasis, you need to be tested for other STIs too.

How is trichomoniasis treated?

Trichomoniasis is easily cured with one of two antibiotics:

These antibiotics are usually a pill you swallow in a single dose.

If you are treated for trichomoniasis, your sex partner(s) needs to be treated too. Do not have sex until you and your sex partner(s) finish taking all of the antibiotics and have no symptoms.

What can happen if trichomoniasis is not treated?

Most people with trichomoniasis have no symptoms and never know they have it. Even without symptoms, it can be passed to others.

If you have trichomoniasis, you are at higher risk of getting HIV (the virus that causes AIDS) if you are exposed to HIV. If you are HIV-positive, having trichomoniasis also raises your risk of passing HIV to your sex partner(s). The Centers for Disease Control and Prevention recommends that women with HIV get screened for trichomoniasis at least once a year.3

What should I do if I have trichomoniasis?

Trichomoniasis is easy to treat. But you need to be tested and treated as soon as possible.

If you have trichomoniasis:

  • See a doctor or nurse as soon as possible. Antibiotics will treat trichomoniasis.
  • Take all of your medicine. Even if symptoms go away, you need to finish all of the antibiotics.
  • Tell your sex partner(s) so they can be tested and treated.
  • Avoid sexual contact until you and your partner(s) have been treated and cured. Even after you finish your antibiotics, you can get trichomoniasis again if you have sex with someone who has trichomoniasis.
  • See your doctor or nurse again if you have symptoms that don't go away within a few days after finishing the antibiotics.

How does trichomoniasis affect pregnancy?

Pregnant women with trichomoniasis are at higher risk of premature birth (babies born before 37 weeks of pregnancy) or a low-birth-weight baby (less than 5 1/2 pounds). Premature birth and a low birth weight raise the risk of health and developmental problems at birth and later in life.

The antibiotic metronidazole can be used to treat trichomoniasis during any stage of pregnancy. Talk to your doctor about the benefits and risks of taking any medicine during pregnancy.

Can I take medicine for trichomoniasis if I am breastfeeding?

You can take the antibiotic metronidazole if you are breastfeeding. Your doctor may suggest waiting 12 to 24 hours after taking metronidazole before breastfeeding. Do not take tinidazole if you are breastfeeding.

How can I prevent trichomoniasis?

The best way to prevent trichomoniasis or any STI is to not have vaginal, oral, or anal sex.

If you do have sex, lower your risk of getting an STI with the following steps:

  • Use condoms. Condoms are the best way to prevent STIs when you have sex. Because a man does not need to ejaculate (come) to give or get trichomoniasis, make sure to put the condom on before the penis touches the vagina, mouth, or anus. Other methods of birth control, like birth control pills, shots, implants, or diaphragms, will not protect you from STIs.
  • Get tested. Be sure you and your partner are tested for STIs. Talk to each other about the test results before you have sex.
  • Be monogamous. Having sex with just one partner can lower your risk for STIs. After being tested for STIs, be faithful to each other. That means that you have sex only with each other and no one else.
  • Limit your number of sex partners. Your risk of getting STIs goes up with the number of partners you have.
  • Do not douche. Douching removes some of the normal bacteria in the vagina that protects you from infection. This may increase your risk of getting STIs.
  • Do not abuse alcohol or drugs. Drinking too much alcohol or using drugs increases risky behavior and may put you at risk of sexual assault and possible exposure to STIs.

The steps work best when used together. No single step can protect you from every single type of STI.

Can women who have sex with women get trichomoniasis?

Yes. It is possible to get trichomoniasis, or any other STI, if you are a woman who has sex only with women.

Talk to your partner about her sexual history before having sex, and ask your doctor about getting tested if you have signs or symptoms of trichomoniasis.

Did we answer your question about trichomoniasis?

For more information about trichomoniasis, call the OWH Helpline at 800-994-9662 or contact the following organizations:


  1. Centers for Disease Control and Prevention. (2015). Trichomoniasis – CDC Fact Sheet.
  2. Centers for Disease Control and Prevention. (2015). Trichomoniasis Statistics
  3. Centers for Disease Control and Prevention. (2013). PDF - Requires Adobe Acrobat Reader CDC Fact Sheet: Incidence, prevalence, and cost of sexually transmitted infections in the United States (PDF, 1.6 MB).

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All material contained on this page is free of copyright restrictions and may be copied, reproduced, or duplicated without permission of the Office on Women's Health in the Department of Health and Human Services. Citation of the source is appreciated.

This fact sheet was reviewed by Centers for Disease Control and Prevention (CDC) staff.

Content last updated: August 31, 2015.

Content last reviewed: March 25, 2014.

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