Download a PDF version of the Chlamydia Fact Sheet [En Español]

What is chlamydia?

Chlamydia is a bacterial infection. It is one of the most common sexually transmitted diseases (STDs) in New York City and around the country. Both men and women can get chlamydia. Most cases occur in women, especially women aged 24 and younger. A young woman's cervix is more vulnerable to chlamydia than an older woman's.

What causes chlamydia?

Chlamydia is spread through contact with an infected person during vaginal, anal, or oral sex.

What are the symptoms of chlamydia?

Many people with chlamydia do not have symptoms. If symptoms ARE experienced, a woman may notice unusual vaginal discharge (drip), pain or bleeding during or after sex, and pain or burning during urination. A man may experience a clear, watery discharge from the penis that comes and goes, and pain or burning during urination. Chlamydial infection of the rectum can cause pain, rectal bleeding, pus or mucous discharge from the rectum or constipation. If you think you've been exposed to chlamydia, your provider can do tests to see if you're infected, whether you have symptoms or not.

(Giving your doctor a chance to find infections that don't have symptoms is one reason it's so important to get regular check-ups, even when you're not feeling sick!)

How will I know if I have chlamydia?

Your doctor or other health-care provider will collect a sample of fluid from the cervix, penis, rectum or mouth with a small swab and have it tested in the laboratory. Chlamydia can also be detected using a urine sample. Sexually active people aged 24 and younger should be tested at least once a year for chlamydia, even if they have no symptoms.

How is chlamydia treated?

Antibiotics can cure chlamydia, often in a single dose. Because the risk of re-infection is high, women who have been treated for chlamydia should be tested again 3 to 4 months after treatment is complete. A person can become re-infected after treatment if exposed to chlamydia again.

What happens if chlamydia goes untreated?

If left untreated, chlamydia can spread and cause severe pain and permanent damage to the reproductive system. It may make both women and men infertile. In women, chlamydia can lead to pelvic inflammatory disease (PID). PID may have no symptoms. When symptoms are experienced, they may include lower belly pain; cramping; burning during urination; pain or bleeding during or after vaginal sex; unusual vaginal discharge; nausea and vomiting, and fever. If left untreated, PID can make it difficult or impossible to get or stay pregnant. It can also lead to "tubal" (ectopic) pregnancies and long-term pelvic pain. Like other STDs, if left untreated, chlamydia can increase a person's chance of getting or spreading HIV. If you have symptoms or think you've been exposed to chlamydia, get examined and treated immediately to avoid any complications.

Do sex partners have to be treated?

Yes. If you're diagnosed with chlamydia, it's important to tell everyone you've had sex with over the past 2 months, so they can be examined and treated, too. Take all your medication as directed, even if you feel better before the medicine is finished. Don't have sex until you and the people you've had sex with have been completely treated and all symptoms have disappeared, or you could infect each other again.

In New York State and New York City, health-care providers are allowed to give extra medication or a prescription to patients diagnosed with chlamydia so that they can give it to their sex partner(s). This is called Expedited Partner Therapy (EPT). For more information on Expedited Partner Therapy (EPT), visit the EPT website.

What if I'm pregnant?

Left untreated during pregnancy, chlamydia can cause premature labor and miscarriage. It can also cause infections in the eyes and the lungs of the newborn baby. All pregnant women should be tested for chlamydia and other sexually transmitted diseases (STDs), including HIV, as early as possible in pregnancy.You should be tested again during your pregnancy if you are at higher risk for getting an STD. For example, you are at higher risk if you have a new partner during pregnancy, or if you have more than one partner. To protect yourself and your baby against HIV and other STDs, use a latex condom whenever you have sex.

How can I avoid chlamydia?

Sexually transmitted infections can be avoided by not having sex. If you are sexually active, you can reduce your risk of getting chlamydia and most other sexually transmitted diseases (STDs), including HIV, by having sex only in a mutually monogamous relationship with a partner you are sure is not infected. If you are having sex outside of such a relationship, you can reduce your risk of STDs by:

  1. Always using a latex condom (or other type of latex barrier) whenever you have sex-vaginal, anal, or oral. Condoms made of "natural" materials, such as lambskin, protect against pregnancy, but not against STDs. If you are allergic to latex, you can use condoms made of polyurethane or other synthetic materials.
  2. Limiting the number of people you have sex with. The more partners you have, the higher your risk.
  3. Avoiding alcohol and drugs when you have sex. Drinking or getting high makes it much harder to remember to use condoms to protect yourself and others. For free, confidential help with a substance abuse problem, call (888) NYC-WELL (888-692-9355), or call 311.

More information

Free, confidential STD exams and treatment, and confidential or anonymous HIV counseling and testing, are available at Health Department clinics in all 5 boroughs of New York City. Health insurance, proof of citizenship, and parental consent are NOT required. See a list of clinics and hours online or call 311.