Hyperthyroid with Pregnancy: Dear all, I am... - Thyroid UK

Thyroid UK

113,106 members131,424 posts

Hyperthyroid with Pregnancy


Dear all,

I am currently 9 weeks pregnant and have just did a bloodtest:

Free T3 (ref. range - 3.5 - 6.5): Results 4.6 pmol/L

Free T4 (ref. range - 9.0 - 25.0): Results 14.8 pmol/L

TSH (ref. range 0.40 - 4.70): Results 0.25 mIU/L

Thyroglobulin Ab (ref. range <4.11): Results 17.10 IU/mL

Thyroid Peroxidase Ab (ref. range <5.61): Results 772.27 IU/mL

I am very shiok that my TPOab is so high. How does it affect my baby and what should I do?

anyone please advise.

9 Replies

You have an Autoimmune Thyroid Disease called Hashimoto's. It is the commonest form of hypothyroidism. The antibodies attack your thyroid gland until you are hypothyroid and they wax and wane. To help reduce the antibodies going strictly gluten-free helps reduce them. Your other results are very good.



Your doctor should refer you to a good Endocrinologist who deals with pregnant women with thyroid disease.

I don't want to worry you unnecessarily but I think this link will be helpful as the more knowledge we have the better.


smileyann in reply to shaws

Thank you so much for your reply. I was actually diagnosed with Hyperthyroid years before and had been on Medication (Carbimazole for a good almost 2 years now before I changed to Prophylthiouracil when I was pregnant). Does this means that my Hyperthyroid has now become Hypothyroid?

You are not hyperthyroid. Someone who is hyperthyroid would have a Free T3 which was over the range, i.e. higher than 6.5, and would usually have a high Free T4 as well, i.e. higher than 25. Both your Free T4 and Free T3 are well in range.

Your high Tg and TPO antibodies show that you have autoimmune thyroiditis (otherwise known as Hashimoto's Thyroiditis).

I wrote a detailed post about Hashi's quite recently. You might want to read it - it's the third reply on this thread :


smileyann in reply to humanbean

Thank you so much for your reply. I was actually diagnosed with Hyperthyroid years before and had been on Medication (Carbimazole for a good almost 2 years now before I changed to Prophylthiouracil when I was pregnant). Does this means that my Hyperthyroid has now become Hypothyroid?

humanbean in reply to smileyann

Not at the moment, although you are probably heading for hypothyroidism.

Since you have Hashi's your thyroid is gradually being destroyed by the thyroid antibodies you have. When enough of it has been destroyed your thyroid won't be able to make enough hormone for you and you will become hypothyroid permanently.

It is common for Hashi's to present with high levels of thyroid hormone to begin with. And 90% of cases of hypothyroidism in the UK are autoimmune in origin.

Since you are pregnant and you have thyroid problems it would be a very good idea for you to get tested for common nutrient deficiencies. Ask your doctor to test your levels of iron/ferritin, folate, vitamin B12 and vitamin D.

If he does the tests ask for a copy of the results. You need the actual result and the reference range. Then create a new thread on here, copy in your results and ask for feedback. If you can optimise your nutrients it will be good for your baby, and will help to keep you feeling as well as possible too.

smileyann in reply to humanbean

I see. So after years of treatment for Hyperthyroidism, I am heading towards the Hypothyroid direction now. Is it normal?

Thanks so much for your recommendation. I shall ask for a nutrient test the next time round :D You have been really helpful! Thank you!

humanbean in reply to smileyann

There are various ways in which people can be hyperthyroid (have an overactive thyroid).

Given your test results, showing high levels of TPO and Tg antibodies, you definitely have Hashimoto's Thyroiditis as one cause.

The antibodies will gradually destroy your thyroid. That can't be avoided completely, but the destruction can be slowed down. It may take many years, or even decades for your thyroid to be destroyed.

Some people find they can reduce their antibody levels by using dietary changes and/or by supplementing with selenium. I discussed this in the link I gave you.

Some people have the bad luck to have both Hashimoto's Thyroiditis and Graves' Disease (GD). People with GD have another form of antibodies. I don't know if you've ever been diagnosed with GD, but if you have it can make thyroid issues a rollercoaster. I don't have it myself, so I can't really help with it.

Katepots in reply to smileyann

I would see if you can get referred to an endocrinologist(hopefully one that understands the thyroid well) to get some proper testing.

What are are you in?

If you email louise.warvill@thyroiduk.org.uk She will send you a list of recommended ones.

Interesting article.


You have Hashimotos Thyroditis which is autoimmune but very common, don't overly panic.

Best to be gluten/Casein(cows milk) free to lessen infllamation

If you can't manage the dairy it is imperative to be gluten free.

Great website for you is


Also Izabella Wentz Hashimotos Protocol book has some easy to understand information.

Dr Datis Khazzarian is the Hashimotos god. His website is excellent and his books have fantastic info, slightly more technical than the others.

I have Hashimotos which was undiagnosed at the time of my pregnancies and I have two healthy children so don't overly panic. Read the books/website info and put a few things in places don't you should be fine.x

I've also done a post listing all the things that help with Hashis.

You may also like...