What it measures
- Thyroid peroxidase (TPO) antibodies
Who it’s for
- Borderline or abnormal thyroid function results
- A family history of thyroid disease
- Other autoimmune conditions, such as type 1 diabetes or coeliac disease
- Planning a pregnancy with a history of thyroid problems
What TPO antibodies mean
TPO is an enzyme your thyroid needs to make its hormones. In autoimmune thyroid disease the immune system makes antibodies against it, slowly damaging the gland. Raised TPO antibodies are found in most people with Hashimoto’s thyroiditis and many with Graves’ disease. Some people have raised antibodies for years with normal thyroid function, but they’re more likely to develop an underactive thyroid over time, so a regular thyroid check is sensible.
Planning a pregnancy?
Thyroid antibodies are worth knowing about before or early in pregnancy, because pregnancy puts extra demand on the thyroid. If yours are raised, your GP or midwife may check your thyroid function more often.
How to prepare
- Drink a couple of glasses of water beforehand: it makes the sample quicker and easier to take.
- No fasting needed. Eat and drink as normal.
- Stop biotin (vitamin B7) supplements, often found in hair, skin and nail products, 48 hours before.
How it works at our Croydon clinic
Book online
Choose your test and a time that suits you. No GP referral needed.
A 15-minute visit
A trained clinician takes a small blood sample at 169 Shirley Road, Croydon. Tell us if you’re nervous.
Results in 1–3 days
A clear report showing each result against its reference range.
Next steps
Share your report with your GP, who can arrange NHS follow-up if anything needs it.
Questions
Do I need this as well as a thyroid function test?
If your TSH is borderline or thyroid disease runs in your family, antibodies help explain the cause. On its own this test doesn’t show how well your thyroid is working, so many people pair it with our Thyroid Function test.
Can thyroid antibodies go away?
Levels can fall, for example after pregnancy, but they often stay raised for life. What matters most is how well your thyroid works over time.
How much is a Thyroid Antibodies (TPO) in Croydon?
£85 at our clinic at 169 Shirley Road, Croydon, including taking your blood sample and your report.
How quickly will I get my results?
Usually within 1 to 3 days, in a clear report showing each result against its reference range.
Pregnant? See our pregnancy blood tests, including NIPT from £295 and the early gender blood test from 6 weeks.