A chlamydia test detects the bacteria that cause chlamydia, one of the most common sexually transmitted infections, using a urine sample or a swab. The standard version used today works by amplifying tiny traces of the bacteria’s genetic material, making it possible to identify an infection even when no symptoms are present. Most results come back within a day.
How the Test Works
The go-to method for chlamydia testing is called a nucleic acid amplification test, or NAAT. It works by finding the genetic material (RNA) of the chlamydia bacteria in your sample, then copying it millions of times so that even a very small amount becomes detectable. This approach replaced older methods like bacterial cultures because it is far more sensitive and can catch infections that would otherwise be missed.
Most chlamydia NAATs also screen for gonorrhea at the same time using the same sample, so you’ll often get results for both infections from a single test.
What Happens During the Test
The collection process is quick and painless. You’ll either provide a urine sample (the first part of your stream, not midstream) or use a swab. For women, a vaginal swab is the preferred option because it catches slightly more infections than urine. Urine samples from women may miss up to 10% of infections compared to vaginal swabs. For men, a urine sample is standard.
In many clinics, you can collect the sample yourself. A provider hands you a swab kit or urine cup, and you do the rest in a private room. If you’ve had oral or anal sex, your provider may recommend a throat or rectal swab as well. A urine test only detects infections in the urinary tract and genitals, so infections at other sites require swabs at those specific locations.
When to Get Tested After Exposure
Timing matters. If you test too soon after a potential exposure, the bacteria may not be present in high enough quantities for the test to detect. The general guideline is to wait at least one week after exposure, which catches most infections. Waiting two weeks catches nearly all of them. Testing earlier than one week risks a false negative, meaning the test says you’re clear when you’re actually infected.
How Long Results Take
Standard lab-based NAAT results are typically ready in about one day. Some clinics offer rapid tests that return results in 90 minutes or less, though these aren’t available everywhere. If you’re testing through a mail-in kit or a busy lab, it may take a few days longer.
Test Accuracy
NAATs are highly accurate. The FDA-authorized at-home test from Visby Medical, for example, correctly identified 97.2% of positive chlamydia samples and 98.8% of negative ones in clinical studies. Lab-based NAATs perform similarly well. False positives are rare, and false negatives are uncommon as long as you’ve waited the appropriate window period after exposure.
One detail worth noting: for women, vaginal swabs and cervical swabs perform equally well, and both outperform urine samples. If you have the option to choose, a vaginal swab gives you the most reliable result.
At-Home Testing
The FDA has authorized the first fully at-home chlamydia test: the Visby Medical Women’s Sexual Health Test. It uses a self-collected vaginal swab and a small testing device that connects to a phone app to display results. The same test also screens for gonorrhea and trichomoniasis. It’s available without a prescription.
This option is currently designed for people with vaginas. For others, at-home collection kits from various telehealth companies let you collect a sample at home and mail it to a lab, though these aren’t the same as a fully self-contained home test.
Who Should Get Tested and How Often
CDC screening recommendations vary by age, anatomy, and sexual behavior:
- Sexually active women under 25: Annual screening is recommended regardless of symptoms or risk factors.
- Women 25 and older: Annual screening if you have a new partner, multiple partners, a partner with other partners, inconsistent condom use outside a monogamous relationship, a previous STI, or a history of exchanging sex for money or drugs.
- Pregnant women under 25: Screening during pregnancy, with retesting in the third trimester.
- Men who have sex with men: At least annually at all sites of sexual contact (urethra, rectum), regardless of condom use. Every 3 to 6 months if on PrEP, living with HIV, or if either partner has multiple partners.
- Heterosexual men: Routine screening isn’t broadly recommended due to insufficient evidence, but it may be appropriate in high-prevalence settings like STI clinics or correctional facilities.
- Transgender and gender diverse people: Screening based on anatomy. Anyone with a cervix who is under 25 and sexually active should follow the same annual screening schedule. Rectal testing should be considered based on sexual history.
- People living with HIV: Screening at the first HIV evaluation and at least annually afterward.
What Happens If You Test Positive
Chlamydia is curable with antibiotics. Your provider will prescribe a course of medication, and it’s important to finish the entire prescription even if symptoms clear up quickly. You’ll need to notify your sexual partner (or partners) so they can get tested and treated too. Untreated partners can reinfect you, which is why this step is critical.
Even after successful treatment, the CDC recommends retesting about three months later. Reinfection is common, and a follow-up test confirms the infection is actually gone. For pregnant women who test positive, the timeline is tighter: a test of cure four weeks after treatment, then another retest within three months.
Why Testing Matters Without Symptoms
Most chlamydia infections produce no symptoms at all, which is exactly why screening guidelines exist. Left untreated, chlamydia can cause pelvic inflammatory disease in women, potentially leading to chronic pain and fertility problems. In men, it can cause painful inflammation of the reproductive tract. Routine testing is the only reliable way to catch and treat these silent infections before they cause lasting damage.