About the Test
Purpose of the test
The purpose of testing is to determine if you have a chlamydia infection.
Because most people with chlamydia don’t experience symptoms, doctors rely on screening tests to detect the majority of infections. Screening tests attempt to diagnose health conditions before you experience symptoms. While doctors may screen for chlamydia on its own, STD screening often involves testing for several STDs at once.
When symptoms associated with chlamydia are present, diagnostic testing is used to confirm or rule out chlamydia as the cause of your symptoms. Because chlamydia can cause similar symptoms to gonorrhea, another common STD, if you have symptoms of chlamydia, your doctor will likely assess you for gonorrhea simultaneously.
What does the test measure?
Chlamydia testing looks for evidence of infection with the bacteria Chlamydia trachomatis. There are several types of tests that can be used to detect chlamydia, including molecular testing, also called Nucleic Acid Amplification Test (NAAT), and cell culture.
NAAT is the preferred method for detecting a chlamydia infection. This type of test detects the genetic material (DNA or RNA) of Chlamydia trachomatis. It can be performed using a urine sample or swab of fluid taken from a site of potential infection such as the urethra, vagina, rectum, or eye.
Traditionally, NAAT takes a day or more to provide results, but there have also been rapid chlamydia tests developed using NAAT methods. Rapid chlamydia tests can often provide a result within 30 to 90 minutes and are typically performed on urine samples or swabs of fluid taken from the vagina or cervix.
Although much less commonly used, cell cultures can help diagnose an infection. Chlamydia cell cultures may be used in children with a suspected infection, when evaluating potential infections in the anus or rectum, and when initial treatment is unsuccessful. In these cases of treatment failure, doctors may use a cell culture to understand which treatments may be most effective for an individual’s infection.
Other types of chlamydia tests are available but are rarely used given the accuracy and availability of NAAT.
When should I get chlamydia testing?
As most people infected with chlamydia do not experience symptoms, doctors rely on screening to detect most cases of chlamydia. Screening guidelines vary based on many factors, including your anatomy, health, and sexual practices. Regular screening for chlamydia is recommended for several groups:
- Women and anyone with a vagina: Those who are sexually active and under the age of 25 should be tested for chlamydia annually, while those aged 25 and older should be screened regularly only if they are at an increased risk of contracting chlamydia.
- Pregnant people: Chlamydia testing is recommended for all pregnant people under age 25 and for those 25 and over with an increased risk of this infection. In addition to initial testing, experts recommend retesting during the third trimester for people with an elevated risk of infection. For pregnant patients diagnosed with chlamydia, follow-up testing is advised four weeks after completing treatment and again within three months.
- Men and anyone with a penis: Those who are gay, bisexual, or have sex with other people with a penis should be tested at least annually. Testing may be recommended every three to six months if you are at an increased risk of contracting chlamydia. Regular screening is not recommended for other people with a penis unless they are at an increased risk of infection.
- People diagnosed with HIV: Sexually active people diagnosed with HIV should be screened for chlamydia during their initial HIV evaluation, then at least annually depending on their risk and local infection rates.
Certain factors increase the risk of contracting chlamydia and may affect how often a person may be screened. Risk factors include having:
- Sex with a new partner
- More than one sexual partner or a partner who has sex with multiple people
- A sex partner diagnosed with an STD
Testing for chlamydia is more frequently conducted in asymptomatic people in settings where infection rates are high, which often includes correctional facilities, adolescent health clinics, the military, and sexual health clinics.
Diagnostic chlamydia testing is recommended for anyone with signs or symptoms of this infection. When symptoms do occur, they may not appear until a few weeks after exposure. Signs and symptoms of chlamydia can vary based on the site of infection but may include:
- Burning during urination
- Abnormal discharge from the vagina, penis, or rectum
- Vaginal bleeding after sex or pain during intercourse
- Pain, tenderness, or swelling in the testicles or scrotum
- Rectal pain
If you’re diagnosed with chlamydia, retesting for this infection is often performed after treatment is complete. You may be tested within three weeks of completing treatment to ensure that treatment was successful or around three months after treatment has ended to see if you have been reinfected with chlamydia.
Finding a Chlamydia Test
How can I get a chlamydia test?
Chlamydia testing is usually ordered by a doctor. If you don’t have symptoms, a doctor can evaluate your risk and suggest an appropriate screening schedule. If you have symptoms of this infection, a doctor will order testing to diagnose or rule out chlamydia.
Testing for chlamydia can be conducted at a hospital, doctor’s office, health clinic, or community health program.
Can I take the test at home?
Testing is usually done by a doctor, but tests are available to detect chlamydia at home. Most at-home chlamydia tests are self-collection kits, which allow you to obtain a swab or sample of urine at home and return it to a laboratory by mail. If an at-home chlamydia test returns positive results, a doctor may suggest confirmation testing with a laboratory-based method.
How much does the test cost?
The cost of chlamydia testing varies based on many factors such as whether you have insurance and where the test is taken.
Chlamydia testing may be paid for by health insurance when ordered by a doctor. Because health plans vary, it’s important for you to discuss the cost of testing, including any copays or deductibles, with your health plan.
If you don’t have health insurance coverage, the cost of testing may include the price of the office visit and sample collection as well as technician fees. Testing may also be available for free or at low cost through community-based organizations and local health departments.
Taking a Chlamydia Test
Chlamydia testing is most often performed using a sample of urine or a swab of fluid collected from the site of potential infection. Both urine and genital swab samples may be collected by you or your medical professional.
Before the test
Before taking a chlamydia test, you should discuss any necessary preparations with your doctor or the health provider conducting the test. Depending on the type of sample required, you may be instructed to not douche or use vaginal creams for 24 hours before the test, avoid taking antibiotics the day before the test, or not urinate for two hours prior to testing to prevent a false negative STD test.
During the test
If a swab sample is needed, a medical professional will use a swab or brush to collect fluid from the site of suspected infection, most often the vagina or urethra. You may experience some discomfort while the swab is being collected, but the process is typically very brief. You may also be instructed by your doctor on how to self-collect swab samples.
To collect a urine sample, you’ll be instructed to urinate into a sterile cup provided by the health care provider. First-catch urine samples are used to test for chlamydia, which means that you should avoid urinating within two hours prior to the test and attempt to collect the first part of your urine stream. Collecting a urine sample usually takes a few minutes.
After the test
Because chlamydia can be transmitted to other people, it is important to avoid having sex until negative test results are received. If you receive a positive test result, you should talk with your doctor about steps to avoid spreading the infection and reduce the risk of future reinfection. No other precautions or restrictions are required after taking a chlamydia test.
Chlamydia Test Results
Receiving test results
The results of a chlamydia test are frequently available within 24 hours after the test sample is collected. For rapid chlamydia testing, results can be returned within 30 to 90 minutes. Chlamydia cell cultures take several additional days because the bacteria has to be grown in the laboratory.
You may receive your chlamydia test results during a follow-up appointment with the health care provider who performed the test, over the phone, or through an electronic medical record.
Interpreting test results
Chlamydia test results are typically reported as positive or negative, indicating whether there was evidence of an infection caused by the bacteria Chlamydia trachomatis.
A positive test indicates that you have a current chlamydia infection that requires treatment with antibiotics. After receiving a positive test result, your sexual partners should also be tested for chlamydia.
A negative chlamydia test means that there is no evidence of a chlamydia infection at the time the test sample was collected.
Helpful questions for your doctor about your results may include:
- What is my chlamydia test result?
- Did my test check for any other STDs?
- Do I need any treatment based on my results?
- How can I talk to my sexual partner(s) about chlamydia?
- When should I be tested for STDs and how often?
