Trichomonas vaginalis symptoms & causes
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.
- 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 be 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
- Painful urination (Dysuria)
- Bacterial vaginosis (BV): Underlying TV should be excluded in patients with BV and recurrent BV.
Men may experience:
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 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.
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
- 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.
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.
References & Further Reading
- BASHH: Successful treatment of highly resistant Trichomonas vaginalis with intravaginal administration of oral metronidazole tablets
- Patient.Info: Trichomoniasis Vaginalis
- BMJ: Trichomonas vaginalis infection is uncommon in the British general population: implications for clinical testing and public health screening
- NICE: Trichomoniasis
- FPA: Trichomonas Vaginalis – Causes, Symptoms, Tests, Treatment
- NHS: Trichomoniasis
- NHS: Trichomoniasis – Prevention
- CDC: STD Facts – Trichomoniasis
- Healthline: Trichomonas Infection: Symptoms, Diagnosis, & Treatment
- Lab Tests Online: Trichomonas Test
- NHS: Trichomoniasis – Diagnosis
- Journal of Clinical Microbiology: Clinical and Laboratory Testing for Trichomonas vaginalis Infection
- Cepheid: Trichomonas Vaginalis (TV) Molecular Test – Xpert TV
- BASHH: BASHH Guidelines
- NHS: Sexually transmitted infections (STIs)