Trichomonas vaginalis

Trichomonas vaginalis, or Trich./TV for short, is a common sexually transmitted infection. Trichomoniasis is the name given to symptoms it produces.

Although not very well known in the UK, Trichomonas vaginalis is the most common non-viral STI in the world. It is less common in the UK, and is most commonly seen in patients from black and ethnic backgrounds and after sexual contact abroad. 

The behaviour of this infection can be best described as ‘men spread, women suffer’. Men often do not get symptoms or develop minimal symptoms, but once they have passed the infection to their female partners who get very distinct and clear symptoms.

Management Guidelines


Further Readings

Related Conditions


  • In England, there are 10x as many cases of Trichomoniasis in black ethnic minority populations than any other group.
  • There are geographic pockets of high prevalence in the UK (Wolverhampton, London).
  • Over 90% of diagnosed Trichomoniasis cases occur in women, but this may be due to men not having access to tests.
  • In 2016, WHO estimated 376 million new infections with 1 of 4 curable STIs: chlamydia (127 million), gonorrhoea (87 million), syphilis (6.3 million) and trichomoniasis (156 million).
  • One is more likely to get exposed to TV compared to chlamydia or gonorrhoea after a sexual contact abroad, or a partner from abroad.


What are the symptoms of Trichomoniasis?

Women may experience:

  • Abnormal vaginal discharge: Foul, fishy or strong smelling 
  • Discharge may be green/yellow in colour
  • Discharge may be thick, thin or frothy
  • Producing more discharge than normal
  • Soreness, swelling or itching around the vagina
  • Less commonly, the inner thighs may become itchy
  • Pain during sexual intercourse
  • Pain upon urination
  • Bacterial vaginosis (BV): Underlying TV should be excluded in patients with BV and recurrent BV.

Men may experience:

  • Pain when urinating
  • Pain during ejaculation
  • Frequently needing to urinate 
  • Thin white discharge from the penis
  • Irritation in the water pipe (not feeling right)
  • Soreness, swelling, redness around head of penis and foreskin (balanoposthitis)
  • Non-Specific Urethritis (TV is one of top 4 causes on NSU)

When do symptoms of Trichomoniasis typically occur?

Symptoms occur within 4-28 days after exposure to the infection. Infection generally persists for fewer than 10 days in males but for much longer duration in women.

    Can I have Trichomoniasis without any symptoms?

    Yes. Some people may have Trichomoniasis without experiencing any symptoms, but are still able to spread the infection to other partners.

    Are symptoms of Trichomoniasis the same as other STIs or infections?

    Itchiness in combination with fishy odour is a classical presentation of Trichomoniasis in women. However many patients do not have any specific symptoms, and other symptoms can be produced by other STIs including Chlamydia and Gonorrhoea, and in fact sometimes in combination.

    Bacterial vaginosis in women, and Non-specific urethritis (NSU) and anaerobic balanitis in men can also be a sign of underlying TV infection.


    Though complications are rare, it may cause premature birth or a baby with a low birth weight in pregnant women. Genital inflammation caused by Trichomonas vaginalis may also increase the risk of contracting or transmitting HIV, as well as other sexually transmitted infections.

    If you are experiencing symptoms of Trichomonas vaginalis, we would recommend getting tested and begin treatment without delay.


    These illustrations show the anatomical sites where the symptoms of Trichomonas vaginalis are experienced.


    How do I get Trichomonas vaginalis?

    • Unprotected vaginal sex
    • Sharing of unclean sex toys (with/without a condom)
    • Genital contact

    There is no evidence that Trichomonas vaginalis can be spread from:

    • Close contact (e.g. kissing and/or hugging)
    • Sharing showers, towels, swimming pools
    • Toilet seats
    • Cutlery
    • It is not thought to be spread through anal or oral sex

    What can increase my chances of getting Trichomonas vaginalis?

    • If you have a greater number of sexual partners
    • Having a partner who has Trichomonas vaginalis
    • You have another sexually transmitted infection
    • If you have unprotected sex

    How can I prevent getting Trichomonas vaginalis?

    • Have protected vaginal, anal and oral sex
    • Use a condom, femidom and/or dental dam with a new partner
    • Only use sex toys that you know are clean
    • You and your new partner get tested before having sex

    Can I pass Trichomonas vaginalis to my child?

    It is very rare to pass Trichomonas vaginalis onto your child by giving birth. Having Trichomonas vaginalis may cause other problems, such as premature birth or low birth weight in infants.


    This is a RT-PCR test which means that the smallest amount of Trichomonas vaginalis DNA can be found in a good quality sample.  


    Window Period

    5 days after sexual exposure (earlier if you’re experiencing symptoms)

    Sample required for men

    For men: urine sample (please don’t urinate 1-2 hours before your appointment) +/- sub-preputial swab

    For women: (self-taken) high vaginal swab

    Time for test results

    Within 3 hours in Birmingham (4 working days in other clinics).


    Method of treatment

    Oral antibiotics


    Length of Treatment:

    Single dose to 5 days


    Further actions:

    1. Abstain from sexual intercourse for 7 days, after beginning treatment
    2. Test & treat your partner(s)
    3. Re-test for Trichomonas vaginalis in 2 weeks

    Page reviewed by Dr. Manoj Malu (Clinical Director)

    Last reviewed date: 3 March 2020
    Next review due: 3 March 2023

    Whilst this content is written and reviewed by sexual health specialists, it is for general guidance only. It is not intended to replace the advice of your clinician.

    If you think you may have Trichomonas vaginalis

    It is important to refer to a healthcare provider as soon as possible. Our experience combined with timely detection can help put you on the right track without delay and avoid complications in the future.

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