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Learn About Chlamydia

Chlamydia is a common and curable sexually transmitted infection (STI). If it isn’t treated, chlamydia can cause fertility problems. The good news is that chlamydia is easy to treat—but most people with chlamydia don’t know they have it, because chlamydia often has no symptoms.

How does someone get chlamydia?
  • Chlamydia is passed on through oral, anal, or vaginal sex. Chlamydia can be passed from one person to another even if the penis or tongue does not go all the way into the vagina or anus.
  • It can also be spread through sharing sex toys, especially if the toys are not cleaned properly before each use.
  • A pregnant person can pass chlamydia on their baby. This can result in eye infections, pneumonia, or other complications.
  • Eye infections can occur when discharge carries the disease into the eye during sex or hand-to-eye contact, but this is rare.
It is important to understand that focusing on signs and symptoms is not very useful. Most women and about half of men don’t have any symptoms. The only way to find out if you have chlamydia is to get tested. If someone does have symptoms, they usually start a few weeks after infection but sometimes don’t show up until months later. Sometimes symptoms disappear after a few days, but this does not mean the chlamydia is gone. It can still be passed on to a sexual partner even if someone has no symptoms. If a person does have symptoms, they may include:
  • vaginal discharge
  • pain or burning sensation during urination
  • pus (thick yellow-white fluid) or watery or milky discharge from the penis
  • pain or swelling of the testicles
  • pain, discharge, or bleeding from the anus
  • soreness and redness in the throat or mouth (for chlamydia infection of the throat)
  • conjunctivitis (inflamed eyelid, for chlamydia infection in the eye)
If the infection spreads to the fallopian tubes (connected to the uterus), symptoms may include:
  • lower abdominal and lower back pain
  • pain during sex
  • bleeding between menstrual periods
  • nausea or fever
This can be a sign that the infection has progressed to pelvic inflammatory disease (see more on this below). Again, most people don’t have symptoms, so getting tested is the only way to know if you have chlamydia.

Chlamydia can be easily cured with antibiotics, but untreated chlamydia can lead to serious health problems.

  • In a person with a uterus, chlamydia can cause a condition known as pelvic inflammatory disease (PID). If PID is not promptly treated and cured, it can cause pain, increase the chance of ectopic pregnancy (pregnancy outside the womb), and eventually lead to infertility (the inability to get pregnant).
  • In a person with a penis, chlamydia can spread to the testicles, causing pain and swelling. There is a possibility that it could affect fertility, but that’s rare.
  • In some cases, chlamydia can cause chronic pain and arthritis (joint pain and swelling), although this is uncommon.
  • Untreated chlamydia can also cause complications during pregnancy and can be passed on to the baby.

A positive rectal chlamydia test, particularly in gay or bisexual men, can sometimes be an indication of a different and more aggressive strain of chlamydia called Lymphogranuloma veneruem (LGV). People testing positive for rectal chlamydia will need to go to a clinic for LGV testing and treatment.

It’s a good idea to get tested if you or a sexual partner:

  • have sex without a condom with a new partner
  • have any symptoms
  • have another STI
  • want to stop using condoms with a partner
  • have a sexual partner tell you that they have, or have recently had, chlamydia

For those who are under 25 years old and sexually active:

  • People with a uterus are advised to do a chlamydia test once a year, and after having sex with new or casual partners.
  • People with a penis are advised to do a chlamydia test once a year if not using condoms with new or casual partners.

It’s possible to be tested within a few days of having sex especially if you have symptoms, but if you have no symptoms and just want a sexual health check-up, you may want to wait up to two weeks after the last sexual contact before getting a test. This is because it can take up to two weeks before chlamydia shows up on a test. Testing too early may miss the infection.

Chlamydia is easy to cure with antibiotics. It’s important to treat chlamydia early so it’s less likely to cause any health problems. You can follow up with a local clinic or health care provider for treatment.

  • If you develop symptoms or have chlamydia in the throat or rectum, you may need further testing.
  • If you have no symptoms, the chlamydia should be cured when you finish your treatment. If you had any symptoms, they should improve in a few days and be gone after 2–4 weeks.
  • Don’t have sex with anyone until you have finished treatment.
  • You should your recent sexual partners know about as they may also have chlamydia and may want to be tested as well.

To help prevent chlamydia and other STIs:

  • Use condoms when you have vaginal or anal sex
  • Get tested for STIs when you have a new sexual partner and before you stop using condoms with a partner
  • If you share sex toys, cover them with a new condom and wash them thoroughly before each person uses them