Trichomoniasis

What is trichomoniasis?

Trichomonas vaginalis is a protozoan, which is a tiny germ, similar to bacteria. It can infect your genital area. That is, the vagina and urethra in women, and the urethra and sometimes the prostate gland in men.

This infection is passed on to other people by having sex (intercourse). This infection does not usually go further into your body and so does not tend to be as serious as some other sexually transmitted infections (STIs).It can also be completely cured, unlike some other STIs.

STIs are passed between sexually active partners - any sexual contact may enable this, not necessarily penetrative sex. Sharing sex toys between partners can also pass it on.

How common is trichomoniasis?

In England in 2016, there were 7,075 new diagnoses of trichomoniasis, compared to 202,546 of chlamydia, 36,244 for gonorrhoea and 31,860 for genital herpes.

As with most STIs, it is most common in younger people under the age of 25. In England, there are ten times as many cases of trichomoniasis in black ethnic minority populations as there are in the general population. Other than in this group of the population, trichomoniasis is uncommon in the UK.

Trichomoniasis symptoms

Symptoms in women

• A vaginal discharge is common. This is typically greeny-yellow and may be 'frothy'. The discharge usually has an unpleasant or fishy smell.

• Your vagina and vulva may be itchy and uncomfortable. The irritation may extend into your groin. Sex may be painful.

• You may have pain in the lower part of your tummy (abdomen).

• It may be sore when you pass urine.

• No symptoms occur in some women. However, you can still pass on the infection even if you have no symptoms.

Symptoms in men

• Discharge from the penis is common.

• It may be sore when you pass urine.

• You may pass urine frequently (due to irritation inside the penis).

• No symptoms occur in most infected men. However, you can still pass on the infection even if you have no symptoms.

How do you get trichomoniasis?

Trichomoniasis is usually passed on by having sexual contact (vaginal, oral or anal sex) with an infected person. As no symptoms may occur in both men and women who are infected, you can pass on the infection without realising it.

Trichomoniasis is the most common non-viral sexually transmitted infection (STI) in the world. It is less common in the UK. However, it is thought that many cases are still not recognised and are not diagnosed. It can be cured with antibiotic treatment.

How to test for trichomoniasis

You can be tested for trichomoniasis at your GP or by visiting a genitourinary medicine (GUM) clinic. It is important to obtain the correct diagnosis, as the same symptoms can be caused by a number of different infections:

• A sample (swab) of the discharge from your vagina or penis is sent to the laboratory to be tested. This may be taken by a healthcare professional, or they may show you how to take one yourself.

• Trichomoniasis is sometimes seen by chance when a smear test is done in women.

• A sample of urine from men may also show the infection.

Trichomoniasis treatment

An antibiotic medicine called metronidazole is the common treatment. You and your partner should be given treatment at the same time and you should avoid having sex (intercourse) for at least one week after receiving your treatment.

Tinidazole is an alternative antibiotic medicine that is sometimes used.

Does my sexual partner need treating?

Yes. Partners should also be treated even if they do not have symptoms of trichomoniasis. You and your partner should be treated at the same time. Anybody you have been sexually active with in the four weeks before your symptoms started should be treated.

Some other points about trichomoniasis

• After you are treated, you may get the infection back if your sexual partner was not treated, or if you have sex with a new partner who has this infection.

• Other STIs are more common in people with trichomoniasis. You (and your partner) may be advised to be tested for other infections.

What are the complications with trichomoniasis?

Pregnancy

If you have untreated trichomoniasis during pregnancy, you have an increased risk of having an early labour and a baby with a low birth weight. You are also more at risk of sepsis after your baby is born.

In women

It may go on to cause pelvic inflammatory disease, and you are more likely to develop another infection called bacterial vaginosis.

In men

Trichomoniasis can, rarely, cause an unpleasant infection of the prostate gland (called prostatitis).

HIV

If you have untreated trichomoniasis, you have an increased risk of developing HIV infection if you have sex (intercourse) with someone who is infected with HIV.

Infertility

In both men and women, trichomoniasis can result in reduced fertility.

How to prevent trichomoniasis

As trichomoniasis is passed on through sexual intercourse, abstinence is the most effective way to prevent it. Otherwise, using a condom is the best way. Use a condom for vaginal or anal sex. For oral sex with a man, use a condom on the penis. For female oral sex, and for women who have genital to genital contact, use a dam (a latex or polyurethane sheet. These are available online).

Limiting the number of sexual partners you have will reduce the chance of contracting it.

Do not douche (actively wash the vulva/vagina with water or soap/other cleansers) - this gets rid of the normal bacteria in this area and may increase the risk of developing infections, including STIs.

Wash sex toys between uses and cover them with a condom before using.

Do not abuse alcohol or drugs - these increase risky behaviours and put you more at risk of contracting an STI.

Have regular STI tests via your local sexual health clinic, particularly before having sex with a new partner - both partners should be tested.

If you are pregnant and have trichomoniasis, or think you might do, get tested and treated to reduce the risk of a premature birth or low-birth-weight baby.