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What Is Trichomoniasis?

Trichomoniasis is an infection of the sex organs that spreads by sexual contact. It’s one of the most common sexually transmitted infections (STIs) or diseases (STDs). It affects both sexes, but is found most often in women aged 16 to 35 years. In the United States, about 2 million women become infected each year. Infection isn’t fatal but can lead to complications, such as infertility; infection of the vaginal skin tissue (cellulitis); and, in men, blockage of the urethra (the tube in the penis that carries urine out of the body). Infection during pregnancy may lead to premature labor and low birth weight.

What Causes Trichomoniasis?

The cause is the single-celled, microscopic parasite named Trichomonas vaginalis, found worldwide.

What Are the Symptoms of Trichomoniasis?

Women can have no symptoms (asymptomatic) or many symptoms. Typical symptoms include foul-smelling or frothy green discharge from the vagina, vaginal itching, and vaginal redness. Other symptoms are pain during sex, lower abdominal discomfort, and need to urinate.

Most men don’t have symptoms. When symptoms occur, they most often are discharge from the urethra, need to urinate, and a burning feeling during urination.

How Is Trichomoniasis Diagnosed?

In women the health care provider will do a pelvic examination to collect samples from the vagina for study. Diagnosis is confirmed by finding the parasite in the sample with a microscope. Growing the parasite in a culture is another way to diagnose infection. Culture results may take 3 to 7 days. Blood tests can also be done to diagnose the parasite.

In men, the health care provider collects samples from the urethra and looks for the parasite with a microscope. The parasite is harder to find in men.

How Is Trichomoniasis Treated?

The health care provider will prescribe antibiotics for treatment. Metronidazole is the best one and can be taken for 7 days. Both partners should be treated at the same time. Metronidazole can cross the placenta, so it isn’t usually used during pregnancy. Side effects include nausea, vomiting, diarrhea, abdominal cramping, metallic taste in the mouth, seizures, and peripheral neuropathy. People should not drink alcohol while taking metronidazole, because flushing, headache, abdominal pain, nausea, and vomiting may occur.

DOs and DON’Ts in Managing Trichomoniasis:

  • DO follow your doctor’s instructions.
  • DO avoid sex during treatment.
  • DO practice safe sex. Use latex condoms if you think there’s a chance of catching an STD. You could catch this infection from your partner.
  • DO limit your sex partners. The more you have, the greater your chance of having sex with someone with an STD.
  • DO call your health care provider if you have burning with urination, vaginal discharge, pain with sex, or side effects from your medicines.
  • DON’T forget, if you have trichomoniasis, your sex partner should also be treated.
  • DON’T forget that even though you were infected with Trichomonas once, you’re not immune. You can get infected again. Take all precautions to prevent another infection.
  • DON’T forget that babies born to infected mothers may get the infection during delivery, although this is rare.

Contact the following sources:

  • Centers for Disease Control and Prevention
    Tel: (800) 311-3435
  • Infectious Diseases Society of America
    Tel: (703) 299-0200
  • National Institute of Allergy and Infectious Diseases
    Tel: (301) 496-5717

Copyright © 2016 by Saunders, an imprint of Elsevier, Inc.

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