Trichomonas vaginalis Dr Rob Hicks Women are more likely to experience symptoms of the infection.

In this article

What is Trichomonas vaginalis? Symptoms

Causes and risk factors Treatment and recovery

Trichomonas vaginalis, a single celled protozoan organism causes infection in the vagina in women and in the urethra in men. In most cases it is transmitted during unprotected sexual intercourse but occasionally the infection can be passed on by sharing towels, washcloths or hot baths.

Women are more likely to experience symptoms of the infection. However, in some cases, there are no noticeable symptoms. When symptoms do occur they may include:

• Change in normal vaginal discharge - thicker or thinner, frothy or yellow/green in colour, fishy odour
• Soreness, itching and inflammation around the vagina
• Pain on passing urine
• Pain during intercourse
• Infection during pregnancy can result in a premature or small baby

Men often have no symptoms. If they do, they may include pain or burning when passing urine and a thin white discharge from their penis that stains underwear. It can cause infection of the prostate. If neither partner has symptoms its possible for them to pass it on unknowingly.

Trichomonas can affect sexually active people of all ages. Practising safer sex by using condoms can reduce the risk of infection. If one partner has the infection, the other should be tested and treated if necessary.

A course of antibiotics such as metronidazole will successfully treat the infection. It's important to abstain from sexual intercourse until the infection has cleared up. You can find a clinic to help with trichomonas by phoning directory enquiries and asking for genitourinary medicine, sexually transmitted infections (STIs) or venereal disease, or visiting www.ruthinking.co.uk, which allows you to search for your nearest STI clinic.

This article was last medically reviewed by Dr Gill Jenkins in June 2009.