Chlamydia is the most common bacterial sexually transmitted infection. Chlamydia infects the cervix (neck of the womb) in women and the urethra, rectum and eyes in both men and women.

Transmission pathways

  • Having sex with an infected partner.
  • Mother to baby during childbirth.
  • Transfer of the infection from genitals to eyes by fingers.

Signs and symptoms


Most women experience no symptoms at all. Possible symptoms include:

  • Increased vaginal discharge
  • Lower abdominal pain
  • A need to pass urine more often
  • Pain on passing urine
  • Irregular menstrual bleeding
  • Painful sexual intercourse
  • Pain and swelling of the eyes if infected


Men are more likely to experience symptoms, but many don’t.

These include:

  • Discharge from the penis
  • Pain and/or a burning sensation when passing urine
  • Pain and swelling of the eyes if infected


Chlamydia is easily treated with antibiotics. Any sexual partner(s) will also need to be treated. It is advisable to avoid sexual contact until treatment of youself and any partner(s) is completed.

Complications in women

  • Pelvic inflammatory disease (PID), which in turn can cause infertility.
  • Ectopic pregnancy (pregnancy outside the womb).
  • Premature birth or miscarriage of pregnancy.
  • Can also lead to chronic (long-term) pelvic pain.

Complications in men

  • Inflammation of the testicles, which can cause infertility

In men and women

  • Reiters syndrome can be due to chlamydial infection, causing inflammation of the eyes and joints and sometimes a rash on the genitals and soles of the feet.


Using a condom or dental dam (or equivalences) reduces the risk of infection.