Trichomoniasis

The Basics

Trichomoniasis (trich) is a common STI caused by a tiny parasite called Trichomonas vaginalis. An estimated 3.7 million people are infected, but because only about 30 percent show symptoms, most people don't know they have it until they get a positive test result.

How You Get It

The parasite gets passed during unprotected vaginal sex (can be from penis to vagina, vagina to penis, or vagina to vagina). Trich usually doesn't affect other areas, like the mouth or anus, which means this is one STD that is relatively uncommon for gay and bisexual men.

What’s It Like?

Here’s where the not-fun part comes in: When trichomoniasis does cause symptoms, they're not exactly pleasant. Men may feel itching or irritation inside the penis, whereas women can experience a gross-smelling vaginal discharge, itching, and burning during urination. Painful sex can also happen for both genders. And pro tip: Anytime you're having painful sex, it's a good idea to stop immediately.

Most people don't know they've got it until they get a positive test result.

How Serious Is It?

"It depends on what your definition of serious is," says Yesmean Wahdan, M.D., the associate medical director at Bayer Women's Healthcare. "If 'less serious' means a disease that can be easily cured, trich falls into that category."

On the other hand, the inflammation that trichomoniasis causes can make it significantly easier to contract a more serious disease like HIV. Infection with Trichomonas vaginalis increases the risk of HIV-1 acquisition. McClelland RS, Sangare L, Hassan WM. The Journal of infectious diseases, 2007, undefined.;195(5):0022-1899. And, as with several STDs, things get more complicated if you're infected and pregnant: Trich is associated with preterm births and other negative pregnancy outcomes.

What Can I Do?

As with many other STDs, you can prevent this one by wearing a condom.

The treatment for trich is easy. It's usually one megadose of antibiotics—metronidazole, tinidazole, or nitroimidazole. FYI: If you are treated with any of these antibiotics, do not drink alcohol. Side effects include extreme nausea and abdominal discomfort. We'll just leave it at that.

“With trichomonas, get treatment and change your behavior while being treated—either with abstinence or condom use," says Yvonne Bohn, M.D., a gynocologist in Santa Monica. And remember that getting it once doesn't make you immune.

Also, trich is not included in your usual STI screening panel (it often just includes chlamydia and gonorrhea). So unless you have symptoms that your doc thinks are in line with trich or you specifically request the test, it won't be included.

The number of people infected with three major STDs is at an all-time high (yikes!). We're tackling common misconceptions about STIs and STDs to help #ShattertheSTIgma. Because getting tested should be NBD.

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