About STIs

Below is a list of the STIs we can test for, and some information about them.


Chlamydia is the most common STI. In many cases, it shows no symptoms, but if left untreated can cause infertility and complications in pregnancy. It can be treated easily with a course of antibiotics. It can be detected in STI tests at around 2 weeks after sex.


Gonorrhoea is a bacterial sexually transmitted infection. It can present in symptoms such as although many people don’t have any obvious symptoms until the infection moves into other parts of the body. Left untreated, it can cause serious health complications. It can be detected in STI tests at around 2 weeks after sex.


HIV is short for Human Immunodeficiency Virus. It is often sexually transmitted but can also be passed on through sharing infected needles and from mother to baby during pregnancy and breastfeeding. HIV can initially have very mild symptoms but left untreated it can have very serious health consequences. It is now very easy to manage through antiviral treatments. People using antiviral treatment effectively can achieve an undetectable viral load which means they are unable to transmit the virus to another person.


HPV is a very common STI which is passed on through vaginal, oral and anal sex skin-to-skin contact and sharing sex toys. Most HPV infections clear from the body but some can cause problems such as genital warts or changes to cells in the cervix. If you have visible warts they can be treated at a sexual health clinic. Some high risk types of HPV that cause changes to cells in the cervix have been linked to cervical cancer therefore knowing if you have HPV can help early detection of any changes.

Genital herpes HSV-1 & HSV-2

Genital herpes is a common STI that can cause blisters around the genital and anal area. Many people who have genital herpes won’t have any symptoms or they will be so mild they will not notice them. Genital herpes remains in the body but can be managed with antiviral treatment if needed.

Trichomonas vaginalis / TV

Trichomonas vaginalis is a sexually transmitted infection. It only causes symptoms in around half of people who have it and men rarely have symptoms. It can cause unpleasant smelling discharge and burning sensations in the genital area. Testing for trichomonas can prevent you from passing it to a partner, even if you have no symptoms of your own.

Syphilis (treponema pallidum)

Syphilis is a less common STI, however the number of syphilis cases in the UK has risen sharply in recent years. Initial symptoms can be mild but left untreated it can have very serious health consequences. It is treated with antibiotics.

Mycoplasma hominis

Mycoplasma hominis is a bacteria that lives in humans usually causes no adverse symptoms. Sudden growth of large cultures can cause symptoms such as painful urination, pain during sex or painful discharge. Some people more than others, such as those with weak or suppressed immune systems or people who have contracted HIV, are more likely to develop an infection. In rare cases the infection can spread to beyond the genitals, affecting organs which can lead to further health complications.

Ureaplasma urealyticum

Ureaplasma Urealyticum is a bacterium found in the urinary tract of both men and women. It's not considered a traditional STI but can be passed through sexual activity or contact with the genitals. Outbreaks or rapid expansion are usually treated with a single dose of antibiotics.

Generally Ureaplasma infection is not harmful and doesn’t cause serious complications or symptoms in humans. For a large portion of the population it causes no problems. However, severe symptoms or rapid expansion or large cultures of the infection can cause irritation and lead to Pelvic Inflammatory Disease in women, resulting in infertility.

Mycoplasma Genitalium (MGen)

Mycoplasma Genitalium (MGen) is a small parasitic bacterium that can infect both men and women, passed through sexual contact or activity. Mycoplasma Genitalium testing is usually undertaken to diagnose a problem if all other tests are inconclusive. For example, very often urethritis that is not caused by either Chlamydia or Gonorrhoea is caused by Mgen. Mycoplasma Genitalium is often asymptomatic, however other symptoms often include those similar to other STIs, such as pain while urinating, pain during sex, painful or discoursed discharge. If untreated, it can lead to further complications such as Pelvic Inflammatory Disease.

Haemophilus ducreyi

Haemophilus ducreyi is a bacteria that can cause of genital ulceration. Common symptoms in both men and women include painful ulcers on the genitals along with genital tenderness and pain while urinating. Further symptoms in women include pain during defecation and rectal bleeding. Infection occurs via physical contact with the infected area, making it transferable during sexual intercourse or activity (including oral and anal sex). Treatment usually consists of a course of antibiotics, however left untreated can lead to complications.