What is chlamydia?


Chlamydia infection in teens: Overview

Chlamydia is a bacterial infection that's spread through sexual contact. It's one of the most common sexually transmitted infections (STIs). It can spread from one partner to another during vaginal, anal, or oral sex.

Most people who have chlamydia don't have symptoms. But they can still infect their sex partners.

Chlamydia is treated with antibiotics. Treatment is important. If chlamydia isn't treated, it can lead to other problems. For example, it can cause a severe infection of the uterus, fallopian tubes, or ovaries. (This is called pelvic inflammatory disease, or PID.).This can make it hard to get pregnant in the future. It can also lead to another kind of infection that causes pain and burning when you urinate (urethritis).

It's easy to get chlamydia again. Condoms can help prevent infections. Not having sex is the best way to prevent any sexually transmitted infection.


Chlamydia (say "kluh-MID-ee-uh") is an infection caused by bacteria. In many cases, it's spread through sexual contact (sexually transmitted). It's treated with antibiotics.

Chlamydia often doesn't cause symptoms. When it does, they may include burning when you urinate, pain during sexual intercourse, or abnormal discharge from the vagina or penis. If chlamydia isn't treated, it can lead to a severe infection of the uterus, fallopian tubes, or ovaries. (This is called pelvic inflammatory disease.)

Some types of chlamydia infection aren't spread through sexual contact. These types can cause a serious eye infection, especially in babies.

What are the symptoms of chlamydia?

Many people don't have symptoms. When symptoms do occur, they usually appear 1 to 3 weeks after sexual contact with an infected person.

Symptoms may include:

  • Abnormal discharge from the vagina, penis, or anus.
  • Pain when you urinate.
  • Pain during sexual intercourse.
  • Pain in the lower belly.
  • Bleeding between periods or after intercourse.
  • Fever and general tiredness.
  • Pain and swelling of the glands at the opening of the vagina or pain in the scrotum.
  • Conjunctivitis.

How is chlamydia treated?

Chlamydia is treated with antibiotics. Early treatment can cure the infection and help prevent long-term problems.

To make sure that the medicine works, you need to take all of it as directed. After you start taking the medicine, you'll need to avoid sex for a week.

As soon as you find out that you have chlamydia, be sure to let your sex partner or partners know. Experts recommend that you tell everyone you've had sex with in the past 2 months. If you haven't had sex in the past 2 months, contact the last person you had sex with.

You and any sex partners need to take the antibiotics. If only one person takes the medicine, you may keep passing the infection back and forth.

How is chlamydia diagnosed?

Your doctor will ask you questions about your symptoms and your sexual history. You may also have a physical exam to look for signs of infection.

Several types of tests can diagnose chlamydia. Most tests use a sample of urine or a swab from the cervix, vagina, or rectum.

Chlamydia can cause serious problems but may not cause symptoms. That's why it's a good idea to get tested once a year if you are at higher risk for getting chlamydia. Talk to your doctor about what testing is right for you.

How can you care for yourself when you have chlamydia?

  • If your doctor prescribed antibiotics to take at home, take them as directed. Don't stop taking them just because you feel better. You need to take the full course of antibiotics.
  • Don't have sex with anyone while you are being treated. If your treatment is a single dose of antibiotics, wait at least 7 days after you take the dose before you have sex. Even if you use a condom, you and your partner may pass the infection back and forth.
  • Make sure to tell your sex partner or partners that you have chlamydia. They should get treated, even if they don't have symptoms.
  • Get any tests your doctor suggests. Your doctor may do tests for other STIs. And you may be advised to get tested again for chlamydia in several months.

What causes chlamydia?

A certain kind of bacteria causes chlamydia. It can spread from one partner to another through different types of sexual contact. This includes vaginal, anal, or oral sex. If you're pregnant and infected, you can pass it to your baby during delivery.

What is chlamydia?

Chlamydia (say "kluh-MID-ee-uh") is a bacterial infection spread through sexual contact. It usually infects the urethra or the cervix. If you treat chlamydia, it won't cause problems. But untreated, it can spread and lead to problems like trouble getting pregnant.

What other health problems can be caused by chlamydia?

Problems from untreated chlamydia can include inflammation of the:

  • Cervix (cervicitis).
  • Urethra (urethritis).
  • Lining of the uterus (endometritis).
  • Uterus, fallopian tubes, or ovaries. (This is called pelvic inflammatory disease.)
  • Glands at the opening of the vagina (Bartholin glands).
  • Prostate (prostatitis).
  • Tubes that hold sperm (epididymitis).

Chlamydia can increase your risk of:

  • Infertility.
  • Chronic pelvic pain. This is caused by scarring of the pelvic organs.
  • Problems during pregnancy. These may include:
    • Pregnancy outside the uterus.
    • Preterm labor.
    • Prelabor rupture of the membranes.

Untreated chlamydia can cause problems in other areas of the body too. It can cause:

  • Conjunctivitis, an infection of the eye.
  • Joint and eye inflammation (reactive arthritis).
  • Inflammation of the mucous membrane of the rectum (proctitis).

Chlamydia can also cause health problems in a newborn.

Chlamydia: When to call

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have sudden, severe pain in your belly or pelvis.

Call your doctor now or seek immediate medical care if:

  • You have new belly or pelvic pain.
  • You have a fever.
  • You have new or increased burning or pain with urination, or you cannot urinate.
  • You have pain, swelling, or tenderness in the scrotum.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You have unusual vaginal bleeding.
  • You have a discharge from the vagina or penis.
  • You think you may have been exposed to another STI.
  • Your symptoms get worse or have not improved within 1 week after starting treatment.
  • You have any new symptoms, such as sores, bumps, rashes, blisters, or warts in the genital or anal area.

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