Chlamydia

Also called Chlamydia trachomatis

Chlamydia is one of the most common sexually transmitted infections. Most people with it have no symptoms, so they do not know they have it. It is easily tested for and treated with antibiotics, but if left untreated it can spread and cause long-term problems, including infertility.

Last updated Nov 9, 2026

What it is

It is passed on through unprotected vaginal, anal or oral sex. Condoms reduce the risk.

Regular testing is recommended for sexually active people under 25 and anyone with a new partner. Partners should be tested and treated too.

Common signs

  • Often no symptoms
  • Pain when peeing
  • Unusual discharge from the vagina, penis or bottom
  • Bleeding after sex or between periods
  • Pain in the lower tummy or testicles

How it is usually diagnosed

  • A urine test or a swab

Records worth keeping

Keeping these together makes each appointment easier, especially when you see a new doctor:

  • Test results and dates
  • Treatment given
  • Retest results if advised

Questions to ask your doctor

  • Do my partners need to be tested?
  • When can I have sex again?
  • Should I be tested for other infections too?

When to get help right away

Call 112 or go to the nearest emergency department if you have:

  • Severe pain in the lower tummy with fever, or sudden severe testicle pain

This page is general information. It is not a diagnosis and does not replace a doctor who knows your history. Medfold keeps your records organised; it does not interpret them.

Sources