In the majority of cases where chlamydia is identified and treated early, the infection will pass without causing any lasting effects.

However, in cases where the infection is left untreated, chlamydia has the capacity to cause long-term health issues and complications.

In women, chlamydia complications may include:

And in men:

Pelvic inflammatory disease (PID)

This occurs is come cases when a chlamydial infection travels to the female reproductive organs, such as the womb and ovaries.

Symptoms of PID may be similar to chlamydia, and include:

  • lower abdominal or pelvic pain
  • pain during sex
  • urinary pain
  • vaginal discharge
  • bleeding after sex
  • bleeding in between periods
  • and heavy or painful periods.

In some cases, it may also cause fever, nausea and vomiting.

Pelvic inflammatory disease can lead to serious health issues, including chronic pain, abscesses, and infertility. It can also raise a woman’s risk of having an ectopic pregnancy. This is where an embryo attaches itself to an area outside the womb, such as the fallopian tubes, and consequently cannot develop.

The condition is typically medicated with antibiotics, but may require follow-up treatment in some cases.

The NHS estimates that about 25 percent of cases of PID are the result of STIs, including chlamydia.

They also state that approximately 10 percent of women who have chlamydia but do not get treatment will go on to have PID inside 12 months.

Chlamydia during pregnancy

Expectant mothers who have untreated chlamydia may risk passing the condition on to their baby, which may manifest as conjunctivitis or pneumonia.

The infection can also cause an expectant mother to give birth prematurely, which again puts the health of the baby at risk.

Chlamydia during pregnancy can often be treated with antibiotics. However these may be of a different variety to those issued in non-pregnant cases, as some antibiotics are not suitable for use during pregnancy.

Tescticle inflammation (epididymitis)

This can occur when the bacterial infection travels to the testes and the epididymis, which is a series of small tubes responsible for the transportation of sperm. This type of infection can cause infertility if not treated.

Symptoms of epididymitis include:

  • pain and tenderness in the testicles
  • swollen testicles due to a buildup of fluid
  • and penile discharge.

There are several reasons why epididymitis might develop; STIs such as chlamydia are just one. Patients are usually treated with a course of antibiotics, and in some cases NSAIDs or other painkillers may be used to ease discomfort.

Reactive arthritis

This condition can affect the joints, eyes or the urethra. It is characterised by pain, inflammation, swelling or stiffness, depending on where it is present.

So for instance, people with reactive arthritis may notice:

  • swollen, stiff or painful joints 
  • symptoms of conjunctivitis, such as eye redness or discomfort
  • or urinary pain.

Those affected may also notice:

  • discomfort in the lower back and buttocks
  • fever
  • weight loss
  • diarrhoea 
  • and mouth ulcers.

It occurs in chlamydia patients, typically a month after the infection has been contracted, when the immune system mistakenly attacks healthy tissue instead of the infection itself.

In many cases the condition will improve within a few months. However, in some instances, the condition may recur after subsequent infections.

Treatment aims at reducing the severity of symptoms, and usually consists of anti-inflammatory medications.

Avoiding complications

The only ways to ensure that you don’t develop complications from chlamydia are to:

  • prevent the infection from occurring in the first place, by practising safe sex, 
  • get tested regularly if you’re sexually active,
  • and commence treatment as soon as possible in the event that you receive a positive test result.

Find out more about chlamydia on our FAQ page.

Page last reviewed:  17/12/2019