Over the past century, scientists in laboratories all over the world have searched for ‘biomarkers’ that can help identify PMS or PMDD in a blood sample. Hundreds of scientific articles have been published in this area, and occasionally a scientist will find a difference in biomarkers between people with and without PMS or PMDD in one sample, but they haven’t been able to repeat that finding in new samples.
Unfortunately, no blood markers have been found so far that can consistently identify people with and without PMDD. Ultimately, scientists believe that PMDD is not an abnormal level of anything in the blood, but instead an abnormal reaction of brain tissue to normal hormone changes - and so the relevant differences may not be detectable in blood from a patient’s arm.
However, there may still be ways to develop a blood test, and work is ongoing. Some scientists are looking at whether genetic activity in the immune cells of the blood might predict similar changes in the brain during hormone changes. This work is in its early stages, and we do not yet know whether a blood test can be developed.
This does not mean that PMDD is not real or does not have a biological cause. It just means that the biomarkers have not been found for developing a blood test for diagnostic purposes.
However, rest assured that we will notify the community as soon as possible if this (or other work) leads to a blood test.
In the meantime, daily symptom ratings in which you record your experience each day across 2 months are the “gold standard” method for diagnosing the disorder.
To read what is known about the biology of PMDD currently: