The most common cause of hypothyroidism (underactive thyroid).
A level of 9 IU/mL falls well within this range, suggesting that your immune system is not currently attacking your thyroid gland. Why Is the TPO Test Done?
The Thyroid Peroxidase antibody test measures the amount of antibodies your immune system produces against an enzyme (TPO) found in the thyroid gland.
While a level of 9 is normal, it should be interpreted alongside other thyroid markers:
Laboratory "normal ranges" can vary slightly. You should always compare your result against the specific reference range provided on your lab report.
If you are experiencing symptoms like fatigue, weight changes, or hair loss despite a normal TPO result, your doctor may look for non-autoimmune causes or monitor your levels over time.
Thyroid Peroxidase Level 9 May 2026
The most common cause of hypothyroidism (underactive thyroid).
A level of 9 IU/mL falls well within this range, suggesting that your immune system is not currently attacking your thyroid gland. Why Is the TPO Test Done?
The Thyroid Peroxidase antibody test measures the amount of antibodies your immune system produces against an enzyme (TPO) found in the thyroid gland.
While a level of 9 is normal, it should be interpreted alongside other thyroid markers:
Laboratory "normal ranges" can vary slightly. You should always compare your result against the specific reference range provided on your lab report.
If you are experiencing symptoms like fatigue, weight changes, or hair loss despite a normal TPO result, your doctor may look for non-autoimmune causes or monitor your levels over time.
