Chlamydia Antibody Test (Serum or Plasma)

Why This Test Is Done

Doctors may order this test if you have symptoms like pelvic pain, unusual discharge, or if you’re at higher risk (e.g., sexually active with multiple partners, pregnant, or part of a sexually transmitted infection screening program). It’s also used to confirm infection after treatment or in asymptomatic individuals.

What to Expect Before the Test

No special preparation is needed. A blood sample is taken from a vein in your arm. The test is usually done in a lab, and results may take a few days to a week, depending on the lab.

What the Results Mean

Positive results indicate the presence of antibodies, suggesting past or current chlamydia infection. Negative results mean no detectable antibodies were found at the time of testing. Follow-up testing or treatment may be recommended based on clinical judgment.

Common Causes of False Results

False negatives can occur if the test is done too early after infection or if the infection is very mild. False positives are rare but may happen due to cross-reactions with other infections or laboratory errors. Discuss your results with your healthcare provider for guidance.