Chlamydia trachomatis is a bacteria that is passed from one person to another through sex. It can cause problems if it's left untreated and so getting a test after unprotected sex is important.

Chlamydia is caused by a type of bacteria called chlamydia trachomatis and it is the most common bacterial sexually transmitted infection in the UK. It won’t cause any problems if it is found and treated early and it is relatively easy to treat.

However, it can cause problems if it is left untreated. These could be infertility (difficulty becoming pregnant), ectopic pregnancy (pregnancy in the fallopian tube) and low abdominal pain caused by pelvic inflammatory disease (PID) in women and people with a vulva. In men and people with a penis, chlamydia can cause painful, swollen testicles (epididymo-orchitis).

Chlamydia is passed from one person to another during unprotected sex- this includes vaginal, oral and anal sex. You can catch it from sex toys if you do not wash them or cover them with a new condom each time they are used. Occasionally it can cause an eye infection if it is passed from the fingers to the eyes. It could also be passed on from a parent to their baby at birth causing a lung or eye infection.

The bacteria infect the cervix (neck of the womb), urethra (tube where the urine comes out), rectum (back passage) and sometimes even the eyes or throat.

You can’t catch chlamydia from hugging, kissing, swimming pools, toilets, sharing towels or sharing cups, plates or cutlery.

Half of people with a penis will not have any obvious symptoms. If they do have symptoms, the most common are tingling or pain when passing urine or discharge (liquid) from the end of the penis.

70-80% of people with a vulva will not have any obvious symptoms. If they do have symptoms, there might be pain passing urine, pain during sex, tummy pain, bleeding between periods or an increase or change in vaginal discharge.

Chlamydia tests are carried out by taking swabs from the penis, vagina, bum or throat. A urine sample can also be used with men. The sexual health clinic will recommend the best test for you depending on whether you have any symptoms, what they are and the type of sex you have.

Yorkshire MESMAC offers pee in the pot Chlamydia and Gonorrhoea tests in most areas, check your local area for more information.

The sexual health clinic will most often give you a one-off dose of antibiotics to treat the chlamydia.

If you are treated for chlamydia, it is really important that your partner also gets treated before you have sex again to prevent reinfection.

Click here for more information on STI testing

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