A genital tract infection that may cause inflammation and a discharge in women or, less commonly, in men

  • Can affect sexually active people of any age
  • Unprotected sex with multiple partners is a risk factor
  • Gender and genetics are not significant factors

Trichomoniasis is an infection caused by the protozoan Trichomonas vaginalis. In women, this infection may cause vulvovaginitis, inflammation in and around the vagina, which may lead to a profuse vaginal discharge and to cystitis. In men, the infection may cause mild inflammation of the urethra (the tube from the bladder to the outside of the body) and occasionally results in nongonococcal urethritis. In most cases, trichomoniasis is a sexually transmitted infection, but an infected pregnant woman may pass the infection to her baby, which may cause the baby to be born prematurely or to have a low birth weight.

What are the symptoms?

Some women have no symptoms, and the infection may only be detected on a routine smear test. If symptoms do occur, they may include:

  • Profuse, yellow, frothy, and offensive-smelling discharge from the vagina.

  • Painful inflammation of the vagina.

  • Itching and soreness of the vulva (the skin around the vagina).

  • Burning sensation on passing urine.

  • Discomfort during intercourse.

Men, usually have no symptoms, but if present, they may include:

  • Discomfort on passing urine.

  • Discharge from the penis.

If you or your partner develop any of these symptoms, go to a clinic specializing in STIs or consult your doctor.

What might be done?

Swabs will be taken from infected areas and tested for the presence of the protozoan. You will probably be tested for other STIs at the same time. If you have trichomoniasis, you will be prescribed antibiotics. Sexual partners should also be tested and treated, even if they have no symptoms. Babies who are born infected do not normally need treatment as the infection usually clears up by itself.

Trichomoniasis protozoan

This magnified image of cells from the cervix shows the presence of Trichomonas vaginalis, the protozoan responsible for causing trichomoniasis.

Can it be prevented?

You can reduce your risk of contracting trichomoniasis by practising safe sex (see Preventing STIs). If you or your partner have been infected, you should avoid spreading the infection further by abstaining from sexual contact until you have both finished your course of drug treatment and your doctor has confirmed that the infection has cleared up completely.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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