trichomonas vaginalis

Trichomonas vaginalis is a common sexually transmitted infection (STI). It is sometimes referred to as trichomonas or trichomoniasis, or shortened to TV. The infection can spread if you have vaginal sex or possibly by sharing sex toys.

What causes trichomonas vaginalis?

Trichomonas vaginalis sometimes called TV is an infection caused by a tiny parasite. The infection is easily passed from one person to another through sexual contact. Anyone who is sexually active can get it. Both men and women can have trichomonas, and pass it on.

Often there are no symptoms, so you may not know you have the infection.

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How is trichomonas passed on?

Trichomonas can be passed from one person to another during sex. In women, the infection is found in the vagina and in the urethra (tube where urine comes out). In men, the infection can be found in the urethra.

Trichomonas is almost always passed on sexually. The infection can spread if you have vaginal sex or possibly by sharing sex toys. Using a condom correctly will reduce your chance of getting or passing on trichomonas.

It is possible for a pregnant woman to pass the infection to her baby at birth.

You cannot get trichomonas from kissing, hugging, from sharing cups, plates or cutlery or from swimming pools or shared baths.

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How can I protect myself from trichomonas?

It is possible to get trichomonas by having sex with someone who has the infection but has no symptoms.

  • Use condoms (male or female) every time you have vaginal sex
  • If you are not sure how to use condoms correctly click here
  • If you're not happy with the condoms you have tried already, why not try a different brand or type? They come in a variety of shapes and sizes
  • Avoid sharing sex toys if they are shared, wash them or cover them with a new condom before anyone else uses them

These measures can also help to protect you from some other STIs such as HIV, chlamydia, and gonorrhoea. If you have trichomonas without knowing it they will also help prevent you from passing it on.

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What are the signs and symptoms?

Up to half of infected people will not have any symptoms at all. If you think you could have trichomonas then go for a check-up. Sexual health clinics don't mind doing check-ups.

Symptoms can show up 3-21 days after coming into contact with trichomonas. If you do get symptoms you might notice:


  • a change in vaginal discharge; this may increase, become thinner, frothy, or change in colour and develop a musty or fishy smell
  • soreness, inflammation and itching in and around the vagina
  • pain when passing urine
  • pain when having sex
  • lower abdominal tenderness


  • a discharge from the penis which may be thin and whitish
  • pain, or a burning sensation, when passing urine
  • inflammation of the glands and foreskin (this is uncommon)

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If I don't get symptoms how will I know if I have the infection?

You won't know unless you have a test. If you or your partner think you might have an infection, you should both have a test. Even if you don't have symptoms you may wish to be tested particularly if:

  • you have had unprotected sex with a new partner recently
  • you or your partner has had unprotected sex with other partners
  • during a vaginal examination your doctor or nurse notices an unusual discharge
  • a sexual partner tells you they have an STI
  • you are found to have another STI

Don't delay seeking advice clinics don't mind doing sexual health check-ups.

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How soon after sex can I have a test?

You should have the test as soon as you think you might have been in contact with trichomonas. For some people trichomonas won't show up on the test straightaway and they may have to wait up to a week for the result.

It is not uncommon to have more than one infection at any one time, so ask about being tested for others. Evidence shows trichomonas infection can increase HIV transmission. Talk to the doctor or nurse about any concerns you might have.

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What does the test involve?

A doctor or nurse will use a swab to collect a sample of cells. They may also ask you to give a urine sample. There are many myths about how swabs are done. A swab looks a bit like a cotton bud, but is smaller, soft and rounded. The swab is wiped over the parts of the body that could be infected and easily picks up samples of discharge and cells. It only takes a few seconds and is not usually painful, though it may be uncomfortable for a moment. Swabs may be used to pick up cells from:

  • the vagina, during an internal examination in women
  • the genital area
  • the urethra

No tests are 100% accurate, but tests for trichomonas should pick up almost all infections in women, and most infections in men. If your test is negative, but your partner is diagnosed with trichomonas, treatment is usually given.

Sometimes trichomonas will be found during a routine cervical smear test. Routine blood tests do not detect infections such as trichomonas. If you are not sure whether you have been tested for trichomonas, just ask.

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What is the treatment for trichomonas?

Treatment of trichomonas is simple and involves taking antibiotic tablets. There are several different antibiotics that can be used. These are taken either as a single dose or a longer course (up to a week). If there is a high chance of you having the infection, treatment may be started before the results of the test are back. There are no treatments that you can buy without a prescription and there is no evidence that complementary therapies can cure trichomonas.

Some of the antibiotics that are used to treat trichomonas interact with the combined oral contraceptive pill. If you are taking the pill tell the doctor or nurse and they can advise you what to do. You should also tell the doctor or nurse if you are breastfeeding. This will influence the type of antibiotic that is given to you.

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How effective is the treatment?

Treatment is very effective. If you take all the antibiotics according to the instructions it is rare for them not to work. Avoid unprotected vaginal sex until you have finished treatment.

You will be advised not to drink alcohol during the treatment and for 48 hours afterwards. This is because antibiotics used to treat trichomonas react with alcohol and can make you feel very unwell.

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Can trichomonas go away without treatment?

For most people trichomonas is very unlikely to go away without treatment.

For some people trichomonas may cure itself, as the body can fight off some infections without treatment. However, if you delay seeking treatment you risk passing the infection on to someone else.

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Will trichomonas affect my chances of getting pregnant?

There is no evidence that trichomonas will affect your chances of getting pregnant.

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What happens if I get trichomonas when I'm pregnant?

Trichomonas may cause problems with a pregnancy. Having the infection can lead to a premature birth or a low birth weight baby. Trichomonas can be passed to a baby during the birth.

Trichomonas can be treated with antibiotics when you are pregnant and when you are breastfeeding they won't harm the baby, but do tell the doctor or nurse that you are pregnant. This will influence the type of antibiotic that is given to you.

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Does trichomonas cause cervical cancer?

There is no evidence that trichomonas causes cervical cancer.

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How will I know how long I've had the infection?

It can be impossible to know, particularly if you don't get any symptoms.

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Should I tell my partner?

If you have trichomonas then it is very important that your current sexual partner and any other recent partners are also tested and treated.

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Do I need a follow-up appointment?

You will need to go back to check that the infection has gone and that you have not come into contact with the infection again. If you have any questions, ask the doctor, nurse or sexual health adviser and make sure you know how to protect yourself in the future.

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Where can I get more information and advice?

Contact The SAFE Project on 0121 440 6655 or 07973 600 849, or come along to the clinic or drop in.

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