Why do Doctors order tests inside the window period?


Hi Dr. Bob,

Thank you so much for the wealth of knowledge you give to this site. I have learned a great deal about HIV that I did not know before.

I have a question regarding testing. Why do some doctors/healthcare centers order patients HIV tests if they are inside their window period? I know obviously some people do not share the right time of their exposure but do Doctors ask for this information? I had a 5 month test done and my doctor just asked if I had intercourse with someone. Also, are urine tests for chlamydia trustworthy? I had one which was negative 4 months after my exposure.

Thanks for your help.




Hi Carl,

HIV-screening tests are ordered during the window period for a wide variety of not very good reasons:

  1. Patients demand it.

  2. Health care providers are unclear on the concept of window periods or limitations of antibody tests.

  3. Patients perform their own tests at home.

  4. Anxiety ("window pain").

There are some appropriate reasons to run some types of HIV tests in certain very specific situations. Plasma HIV RNA can be useful in diagnosing acute retroviral syndrome prior to seroconversion in certain situations. However, 2% to 9% of people without HIV infection have false-positive results and this type of testing is not appropriate for routine HIV screening for a variety of reasons.

Regarding urine tests for Chlamydia, yes, they are trustworthy.

Be well, Carl.

Dr. Bob