Trichomoniasis is a type of sexually transmitted disease (STD) that's caused by infection with a parasite called Trichomonas vaginalis.1 Men and women can be affected, although women tend to develop it more commonly.

The parasite is spread through sexual contact, typically during vaginal sex between a man and a woman or between two women. Once spread, the parasite will generally affect:

  • The vulva, vagina, and/or cervix (in women)
  • The urethra (in men and women)

It's rare for trichomoniasis parasites to affect other body parts, including the mouth or anus.

How Common is Trichomoniasis?

You may be surprised to know that trichomoniasis is thought to be the most common curable STD in the United States.1 The Centers for Disease Control and Prevention estimate that around 3.7 million people are currently living with it.

This STD can affect people of all ages, as well. A 2011 survey out of John Hopkins University found that trichomoniasis affects women over 40 twice as much as previously thought.2

Trichomoniasis Signs and Symptoms

The majority of people who are living with trichomoniasis have no symptoms at all. It's been estimated that only about 30% of people with this STD will develop any signs or symptoms. If present, they may range from mild to severe and can include:

  • Burning during urination
  • Itching, irritation, redness, and/or sores in the genitals
  • Burning after ejaculation (in men)
  • Discharge from the penis (in men)
  • Abnormal changes to a woman's normal vaginal discharge, including increased or decreased volume or discharge that is greenish or yellowish with an unusual fishy odor

These symptoms (if present) will generally show up around 1 to 4 weeks following initial exposure to the parasite, although it's possible for symptoms not to show up until much later. As mentioned, it's far more likely not to have any symptoms at all.

It may be helpful to remember that even if a person with trichomoniasis doesn't have any symptoms, it's still possible for them to pass the STD onto their sexual partners. Symptoms can also come and go.

Complications of Trichomoniasis

Having one STD often increases your risk of contracting another STD, and this seems to be the case for people living with trichomoniasis.1 For example, genital inflammation and sores caused by trichomoniasis can make a person more likely to acquire human immunodeficiency (HIV) if they are exposed to it, because the symptoms makes it easier for the virus to gain access into a person's body.

Untreated women are at risk for developing pelvic inflammatory disease (PID) if the parasite infects upper parts of her reproductive tract. PID increases the risk of reproductive complications like infertility and ectopic pregnancies.2 Pregnant women with trichomoniasis also have an increased risk of having a premature or low-birth-weight baby.

Lastly, having symptomatic trichomoniasis can also negatively impact a person's mental health and impair their ability to enjoy and feel comfortable during sex.

Treatment of Trichomoniasis

If left untreated, trichomoniasis can last for years, which will increase the risk of subsequent complications. Because of this—and especially because of how common trichomoniasis is—it's important to be screened regularly for this STD if you're sexually active, and especially if you have multiple or new sexual partners.

Diagnosis can be made via a simple lab test. People who have trichomoniasis can be treated with oral precription antibiotics, such as metronidazole or tinidazole. While this treatment can effectively cure a person of the STD, it doesn't prevent them contracting the STD again in the future.

In fact, about 20% of people who are treated for trichomoniasis are re-infected within 3 months.1 It is possible to reduce the risk of re-infection, however:

  • Take all medications as prescribed
  • Wait at least 7 to 10 days after treatment before resuming sexual activity
  • Ensure all sex partners are tested and, if necessary, treated
  • Practice safer sex practices, including sexual monogamy with a committed partner and the use of condoms

Are you well-informed about your sexual health? Getting regularly tested for STDs is the smart thing to do if you're having sex with new or multiple partners. If you're ready to get screened and are interested in doing it in the privacy of your own home, check our STD test kit.