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Chlamydia Infections

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

Last synced 8/10/2026Status: primary verified

What is chlamydia? Chlamydia is a common sexually transmitted infection (STI). It is caused by bacteria called Chlamydia trachomatis . Anyone can get chlamydia. It often doesn't cause symptoms, so people may not know that they have it. Antibiotics can cure it. But if it's not treated, chlamydia can cause serious health problems. How is chlamydia spread? You can get chlamydia during oral, vaginal, or anal sex with someone who has chlamydia. Chlamydia can also be passed to the baby during childbirth . If you've had chlamydia and were treated in the past, you can get re-infected if you have unprotected sex with someone who has it. Who is more likely to get chlamydia? Chlamydia is more common in young people, especially young women. You are more likely to get infected with chlamydia if you don't consistently use a condom or if you have multiple partners. What are the symptoms of chlamydia? Chlamydia doesn't usually cause any symptoms. So you may not realize that you have it. But even if you don't have symptoms, you can still pass the infection to others. If you do have symptoms, they may not appear until several weeks after you have sex with someone who has chlamydia. Symptoms in women include: Abnormal vaginal discharge, which may have a strong smell A burning sensation when urinating If the infection spreads, you might get lower abdominal (belly) pain , pain during sex, nausea , and fever . Symptoms in men include: Discharge from your penis A burning sensation when urinating (peeing) Pain and swelling in one or both testicles (although this is less common) If the chlamydia infects the rectum (in men or women), it can cause rectal pain, discharge, and bleeding. How is chlamydia diagnosed? There are lab tests to diagnose chlamydia. Your health care provider may ask you to provide a urine sample. Or your provider may use (or ask you to use) a cotton swab to get a sample from your vagina to test for chlamydia. Who should be tested for chlamydia? You should go to your prov

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This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.