Name of disease (also known as)Chlamydia trachomatis (The Clam, The Clap)


Common/UncommonChlamydia is the most common STI, particularly in those under the age of 25.


SeverityIt is highly infectious and if left untreated then it can lead to a range of more severe symptoms of infertility, pain in the pelvis in females and testicular pain for males.


How it is transferred: Vaginal, oral and anal sexual contact. It is also thought that it can be transmitted via sex toys that are shared and not cleaned or protected using a condom.


Symptoms: 50% of men and 80% of females do not have any symptoms so if you have unprotected sexual contact it is best to get tested and be sure.



  • Pain when passing urine
  • Painful testicles
  • Milky white fluid coming out the penis without pain and spontaneously



  • Bleeding in between periods
  • Heavier periods than are normal for you
  • Pain and/or bleeding during and/or after sex
  • A discharge that is not normal/increased quantity for you
  • Pain in the lower abdomen
  • Pain on passing urine  


Testing method: Visit your local genito-urinary clinic, sexual health clinic or GP. Testing is confidential and results are often given in the way you prefer (text, email, phone call).

If no symptoms: Males urinate in tub and blood sample taken. Females do a self-taken swab and blood is taken. 

Symptoms: Health professional takes a painless swab of penis/vagina and a blood sample is taken. Samples can also be taken of the anus and throat, depending on what type of sexual contact you were involved in.


Treatment: A single dose of an antibiotic tablet or a longer 7 day course of antibiotics if the doctor or nurse thinks you need it.


How it can be prevented: Barrier methods of contraception (Condoms, Femi-doms and Dental-dams). Hormonal methods of contraception (the pill) don’t offer any protection.


Noteworthy points:    

  • Can affect fertility in both male and females if left untreated.
  • It’s advised not to have sex until 7 days after treatment to allow the medication to work.
  • Don’t have unprotected sex if you suspect you might have an STI and are waiting for results of the test.
  • Follow-up test is done at 3 months to check the infection has all gone, swabs as said above are done.
  • Get yourself checked as soon as you can if you suspect you might have an STI e.g. after having unprotected sex.


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