Trichomonas Test
Note: this site is for informational purposes only. To view test results or book a test, use the NHS app in England or contact your GP.
A trichomonas test detects infection with the parasite Trichomonas vaginalis using samples such as a vaginal swab or a urine sample, depending on the individual. It is used to diagnose trichomoniasis, a sexually transmitted infection that can affect the genital or urinary tract.
Why get tested?
To diagnose an infection with Trichomonas vaginalis
When to get tested?
If you have symptoms of infection or have had unprotected sex and are concerned you may be at risk of an STI (sexually transmitted infection).
Sample required?
A swab of secretions taken from the vagina in women or the urethra in men. A urine sample can also be used in men.
Test preparation needed?
None
Common questions
The secretions collected on the swab are examined under a microscope to detect the presence of Trichomonas vaginalis.
Your doctor may request the test if you complain of symptoms, such as vaginal discharge or pain on urination or have recently had unprotected sex. If you have an infection with another sexually transmitted infection, your doctor might test for trichomonas as well.
A positive test indicates an active infection that requires treatment with a course of antibiotics. You will usually have to take the antibiotic twice a day for 5–7 days.
An infected person is at greater risk of getting other sexually transmitted infections, so the doctor may also test for these. It is important that your current and other recent sexual partners are made aware, so that they can also get tested.
Trichomonas infection can affect pregnancy, contributing to premature birth and low birth weight. You should inform your doctor if you may be pregnant. The doctor may medically manage a woman who is infected and in her first three months of pregnancy differently.
In women, the most common symptoms include a foul-smelling green discharge from the vagina and itching or redness in and around the vagina. Other symptoms can include abnormal vaginal discharge, an unpleasant fishy smell, pain during urination or when having sexual intercourse. Symptoms for men can include , soreness, swelling or redness around the penis, pain during ejaculation, discharge, increased urination or pain during urination.However, 50% of women and the majority of men with T. vaginalis infections have no symptoms.
The parasite is transmitted through sexual contact.
It is usually treated with an antibiotic called metronidazole. All current sexual partners must be treated at the same time or the patient is likely to become re-infected.
- Use a latex condom properly, every time you have sexual intercourse, with every partner.
- If you are infected, your sexual partner(s) should be treated. This will prevent you from getting re-infected.