Chlamydia is a bacterial infection. It's one of the most common sexually transmitted infections in the UK.

How do you get chlamydia?

The most common way to get chlamydia is by having unprotected vaginal, anal or oral sex (sex without a condom). Other ways of getting chlamydia include:

  • sharing sex toys that aren't washed or covered with a new condom each time they're used
  • infected semen or vaginal fluid getting into your eye

Chlamydia can also be passed by a pregnant woman to her baby.

Symptoms of chlamydia

Most people with chlamydia don't notice any symptoms and don't know they have it.

If you do develop symptoms, you may experience:

  • pain when peeing
  • unusual discharge from the vagina, penis or rectum (back passage)
  • pain in the lower tummy, bleeding after sex, and bleeding between periods
  • pain in the testicles
  • red, sticky eyes

Testing for chlamydia

If you think you have chlamydia you should make an appointment with your GP or local sexual health services.

The test for chlamydia is simple, painless and very reliable. It involves sending a sample to a lab for analysis from the area of the body thought to be infected.

In the majority of cases you don't have to be examined by a doctor or nurse and can often collect the sample yourself.

The 2 main ways the sample can be collected are:

  • using a swab – a small cotton bud is gently wiped over the area that might be infected, such as inside the vagina, throat, or inside the anus
  • peeing into a container – this should ideally be done at least 1 or 2 hours after you last peed

Online appointment booking

You may be able to book an appointment for an STI test online using the online booking system. This varies for different NHS board areas.

Treating chlamydia

Antibiotics will get rid of the chlamydia infection.

You should also avoid having sex until one week after you and your partner(s) have been treated. This includes oral sex and sex using a condom.

If chlamydia is left untreated you may pass it onto other sexual partners.

Chlamydia can occasionally lead to more serious problems such as pelvic inflammatory disease (PID). This is when the infection gets into the womb and fallopian tubes. PID could lead to problems in the long term, such as infertility and ectopic pregnancy.

Infection can sometimes spread to the testicles causing pain, swelling and inflammation.

Avoiding passing on chlamydia to a partner

To avoid passing on chlamydia to your partner(s) you shouldn't have sex until one week after you and your partner(s) have been treated.

It's good practice to get a sexual health check-up when you change sexual partner.

If you have tested positive for chlamydia, all of your sexual partners in last 6 months should be offered a test.

Reducing the risk of chlamydia

The best way to prevent all sexually transmitted infections is to practice safer sex. This means using a condom for vaginal, anal or oral sex.

Other STIs

If you have been diagnosed with chlamydia it is recommended you have a test for all STIs including:

Last updated:
01 February 2023

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