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    The Common STD You May Not Know About

    woman in bathroom

    I remember quite vividly the first time I saw trichomonas when I was a medical student. As my supervising physician hovered over my shoulder, she firmly instructed me to look through the microscope and tell her what I saw. I was nervous, having little experience with microbiology, but when I looked through the eye piece I saw a slide teeming with activity. Microscopic creatures that looked like stingrays darted back and forth, whipping their long tails about as the sped past the boring stationary cells on the slide. Watching the trichomonads swim back and forth was pretty cool, until it dawned on me that this meant our nice patient had a sexually transmitted disease.

    Trichomonas is a protozoan, or a single-celled parasite, that thrives in the moist environment of the vagina. It is an extremely common STD, effecting approximately 8% of women in the U.S. Trichomonas is an extremely contagious STD and often women have the infection for several months before symptoms develop. Contagious and stealthy – no wonder it’s so prevalent.

    The most common symptom of trichomonas is copious, frothy vaginal discharge that is often so heavy a panty liner is needed. I’m talking about some serious vaginal discharge here, like “running down the leg when you stand up” kind of discharge. I’ve had several patients think their water was broken only to come in to the hospital and get the unfortunate diagnosis of trichomonas. Sometimes the discharge is white but can also be a yellow-green color. Trichomonas won’t kill you, but it can cause other symptoms besides the gross discharge, like painful urination, pelvic cramping, and bleeding after sex. It has also been associated with infertility and an increased risk of contracting HIV. In pregnancy, it has been associated with preterm delivery and it can also be spread to the baby at the time of delivery (in addition to embarrassing “did my water break?” visits).

    The CDC recommends that all women complaining of vaginal infections be tested for trichomonas if they have new or multiple sexual partners. To test for trichomonas, we start by looking at the vaginal discharge under the microscope, but we now know that we miss the little swimmers about 40% of the time by simple microscopy. They can be really tricky to catch sometimes. Newer lab tests, using a swab of vaginal secretions, are up to 99% accurate and are indicated if the microscopy is negative.

    The other good news is that trichomonas is usually easy to treat with simple antibiotics. However, because it is so contagious, it is important to have all sexual partners fully treated – and then, wait an additional 7 days before resuming sexual contact. Trichomonas can also live on sex toys, so it is important to thoroughly clean them (the dishwasher is best… but not with your dishes) to prevent reinfection.

    Trichomonas is best prevented by maintaining a mutually monogamous relationship and, secondarily, by consistent condom use. Men have lower rate of trichomonas than women and rarely have obvious symptoms of the infection. When they do, their symptoms my include irritation of the urethra or prostate.

    If you have a persistent frothy discharge, see your provider for testing. And make sure you are getting trichomonas testing with your regular STD screening. If you do have it, you can breathe easy – it isn’t life threatening. But it is uber contagious, so make sure you are thoroughly treated.


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