Reviewed/Revised Apr 2023
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What is chlamydia?

Chlamydia are bacteria that can cause several kinds of infection. One common chlamydia infection is a sexually transmitted infection (STI). An STI is an infection that is spread from person to person by sexual contact.

A chlamydia STI can affect your genitals and, in women, your fallopian tubes and ovaries. Fallopian tubes connect your ovaries (sex organs that hold your eggs) with your uterus.

Sometimes, having oral sex with someone who has chlamydia can cause a throat infection with chlamydia. Anal sex can cause the infection in your rectum (where your poop is stored).

  • You can get chlamydia through vaginal, oral, or anal sex with an infected person

  • A pregnant woman can spread chlamydia to her baby’s eyes or lungs during birth

  • You may not have any symptoms even if you're infected, or your symptoms may take many weeks to bother you after you're infected

  • In men, symptoms include discharge from the penis and a burning feeling in the urethra (tip of penis) when urinating (peeing)

  • In women, symptoms include feeling the need to urinate often, pain when urinating, and having a thick, yellow liquid come from your vagina (vaginal discharge)

  • Women who don't get treatment may have permanent damage making it difficult or impossible to have a baby

  • If you're sexually active, talk to your doctor about a screening test for chlamydia

  • Doctors treat chlamydia with antibiotics

A woman who has chlamydia and doesn't get treated can get pelvic inflammatory disease (PID). PID is an infection in your uterus, the fallopian tubes, or both. PID can also spread to your ovaries and your bloodstream. PID can damage your reproductive organs and make it difficult to have a baby.

A man who has chlamydia can develop epididymitis, an infection of the epididymis. The epididymis is the coiled tube on top of each testicle. Epididymitis causes pain and swelling in your scrotum.

What are the symptoms of chlamydia?


Many women don't have any symptoms or have only a few symptoms:

  • Feeling like you need to urinate more often than usual

  • Pain when urinating

  • Yellow fluid from your vagina

  • Pain during sex

  • Sometimes serious pain in the lower belly


Most men have symptoms:

  • Burning and pain when urinating

  • Feeling like you need to urinate more than usual

  • Clear or cloudy discharge (thick fluid) from your penis

  • Opening of your penis is red and crusted shut in the morning

  • Painful swelling of the scrotum on one or both sides (if you have epididymitis)

Women and men

If your rectum is infected, you may have pain and have a yellow discharge from your anus (where your poop comes out).

If your throat is infected, you usually won’t have any symptoms.

You can still pass the infection to your partner even if you don't have symptoms.

How can doctors tell if I have chlamydia?

  • Doctors suspect chlamydia based on your symptoms

  • To tell for sure, they’ll do tests on your urine or on a sample from your penis, vagina, throat, or rectum

Your doctor may put a small cotton swab in your penis, throat, or rectum to get a sample of fluid to test. If you're a woman, your doctor will look in your vagina using a plastic speculum and swab the discharge from your cervix (lower part of your womb that opens to your vagina).

If you're pregnant or are at higher risk of having chlamydia, your doctor may do a urine test for chlamydia when you don't have any symptoms. Women are at higher risk if they:

  • Are having sex and are under age 25

  • Have ever had an STI

  • Do risky sexual activities (such as engaging in sex work, having a partner who engages in sex work, having many sex partners, or not using condoms regularly)

  • Have a partner who does risky sexual activities

Men are at higher risk if they:

  • Have had sex with a man in the past year

Doctors may also test your blood or urine for other STIs because many people have more than one STI.

How do doctors treat chlamydia?

Doctors will:

  • Give you and your sex partner antibiotics

  • Tell you to avoid having sex until you take all of your antibiotics to prevent spreading chlamydia

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