TSH testing when pregnant?

[Lilly12255]

Are there any official guidelines on how often GO should do TSH tests for people with Hashimoto/subclinical hypothyroidism once pregnant?

[humanbean]

Source : btf-thyroid.org/pregnancy-a...

Go to the above link and check out the whole page - but this is one part of the page that specifically answers your question - the bit in bold.

If you have an underactive thyroid (hypothyroidism)

If you are planning a pregnancy you should speak to your GP to arrange thyroid blood tests and ideally aim for a Thyroid Stimulating Hormone (TSH) level of less than 2.5mU/l at the time of conception

It is recommended that your TSH should be less than 2.5mU/l in the first trimester of pregnancy and less than 3.0mU/l after that

As soon as you know you are pregnant it is usually recommended that your levothyroxine is increased immediately by 25-50mcg daily. You should then contact your GP and arrange to have a thyroid blood test

If you have had thyroid cancer and are already on doses of levothyroxine that keeps your TSH level suppressed, you will probably not need to increase your levothyroxine but you should discuss this with your GP or specialist

Thyroid blood tests should be checked every four to six weeks during pregnancy and with a further test a few weeks after delivery. It may not be necessary to test so frequently in later pregnancy if your thyroid levels are stable

After delivery you will probably need to return to your pre-pregnancy dose of levothyroxine and patients taking levothyroxine for subclinical hypothyroidism may be able to stop treatment. You should discuss this with your GP or specialist before making any changes to your dose

Breastfeeding is safe while taking levothyroxine

[Lilly12255 in reply to humanbean]

Thanks a lot for sending this. One follow up question: my TSH seems to be very unstable (was 1.2 in Nov 2020 and rose to 3.5 in June 2021). Is there a rule on testing frequency to stabilise TSH ahead of pregnancy? My GP tests me every 6 months and clearly it’s not enough as my functions keep deteriorating due to antibodies.

[HashiFedUp]

Try NICE guidance. It might be in there somewhere. I would say every six weeks or so. As when we have medication changes, we test after six weeks. Also look out for baby’s size - if you’re measuring small, then it could be the hashimotos. I had a 5lb baby but was undiagnosed! If you’re diagnosed then thats great : )

Lastly, your pregnancy should be managed by a consultant (not the standard midwife team) because of hashimotos!

[Lilly12255 in reply to HashiFedUp]

Sadly, I never had the time to see a OBS because no pregnancy has survived 6 weeks so far, I miscarried them all. Never had adequate TSH level as my GP stops testing as soon as I am < 2.5 and then it goes up without me knowing... It's quite distressing. All they have to say on miscarriages is "just try again".

That's all well said but I am now nearly 44, after years of miscarriages due to GP failure to bring my TSH down to < 2.5 at time of implantation...

[HashiFedUp in reply to Lilly12255]

You need to go private in that case! I did and it was the best £150 i ever spent. x

[Wetsuiter]

So sorry to hear that