Hi, wondering if anyone can shed some light for me. I’m 28 weeks pregnant, had thyroid tested 6 weeks ago -T4-10.6 (ref range 11-22) and repeated T4 this week at 10.3 (ref range 11-22). Both times I’m told TSH is within normal range and need repeat bloods again in another 6 weeks.
My question is, should I be concerned? I’m feeling very tired, like walking through mud alot of the time (!), and originally had the bloods taken due to having palpitations. Not sure if I need to investigate these thyroid results further or just accept I need to wait another 6 weeks to be tested again as they are only slightly under range and TSH is normal.
Any thoughts appreciated!
Thanks
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sunshinebright
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Yes, you should be concerned - and so should your doctor! Do you have a diagnosis of thyroid problems? Or is this the first thyroid test you've had? Didn't you have one when you first got pregnant?
There's no such thing as 'normal' and no such thing as 'slightly under range'. You don't say what your TSH level is, but if it's above 2 then it's too high. Your FT4 should be at least mid-range.
Not sure how to ask this question, but how pregnant are you? If you're in your first trimestre then the FT4 could be low because the baby is taking it. After the first trimestre the baby will have developed his own thyroid so won't be reliant on yours anymore. But, given that many women develop thyroid problems during pregnancy this should really be treated.
I have no diagnosis of thyroid problems. They were last tested in November 2022 because I was trying to conceive and they ran some tests-GP receptionist told me today that T4 last year was 17.6 (range 11-22).
I had a thyroid test 6 weeks ago due to palpitations, feeling breathless on going up stairs and very tired. That’s when I was told T4 was 10.6 (range 11-22) but not to worry as TSH normal (no one told me the exact result). I had to have them repeated this week. Result T4-10.3 (ref range 11-22). I have only spoken to the receptionist so far as GP didn’t request to see me, only wants me to recheck bloods in another 6 weeks. Tried to book an appointment to discuss but none available (apparently more released tomorrow!). Receptionist said I only needed to know the T4 result as that was the one slightly out of range!
I am 28 weeks pregnant.
To be honest I feel a bit lost with this and not sure how to proceed. Any advice?
Receptionist said GP had spoken to hospital today and the notes said they advised to reassure no thyrotoxicity at present and to re test in 6 weeks. I don’t even know what this means!
You need to know what the TSH is as the guidance is for TSH to be 2.5 or under during first trimester, and changes in other trimesters.
I don’t wish to cause alarm, but like you, I had tests before pregnancy and was told all was within range. Then during pregnancy it was not . I became very ill very quickly, and so far it’s been a long road back. In my view, yes, you should be worried as that T4 is quite low, in fact, below range, and may explain your symptoms.
Generally, many GPs without input from Endocrinology would start treatment in pregnancy if the TSH is struggling. Hence you need to know what it is. Go back to discuss with GP and ask to have antibodies tested if not already as this may help them decide better if you should have treatment.
Again, I don’t want to cause alarm as the last thing you need is treatment if it is not required.
By 28 weeks the baby should not be as reliant on your thyroid hence that T4 is not great. I would urge you to take more control at this point as GPs and other professionals, along with national guidance are poor in this area.
I’ll ask for antibodies to be tested. As far as I’m aware it is only TSH and T4 that has been tested.
And check the result of the TSH. However if the GP says it’s ‘within normal range’, what can I do? Would they still treat for hypothyroidism if ‘normal range’. I understand that it is more subtle than this but the impression I have is ‘computer says normal’ .
I will ring for an appointment tomorrow. I’m also due to see antenatal consultant tomorrow (unrelated to this-previous c section), I’ll ask them too.
Out of interest, were you treated for hypothyroidism with low T4 and ‘normal’ TSH in pregnancy?
My TSH was raised but within range, and my T4 was in the lowest end but within range and I was started on a full replacement dose immediately. However, my GP also tested antibodies and my thyroid had been under investigation prior to pregnancy. I don’t want to bog you down with the details, but treatment decisions vary based on the GP. Recently someone posted that they were able to get a diagnosis and treatment based on just one test result which isn’t part of guidance. What matters is your symptoms. I would also have your vitamins level tested including Vitamin D, B12, Ferritin, CRP for inflammation, and Folate.
It’s so unclear. I read earlier today online that low T4 and ‘normal’TSH can indicate pituitary problems and thyroxine not recommended. It’s hard when you are putting all your trust in the GP to know the right thing to do and have very little knowledge yourself. Feel stupid for just accepting this was ok now.
I have had Vitamin D checked due to symptoms (normal, no idea of actual result), CRP was slightly up on results from 6 weeks ago (again don’t know result). Haven’t had B12, ferritin or folate.
I had results from my 28 week antenatal bloods last week and they said haemoglobin was 119 dropped from 133 at 8 week booking appointment and haematocrit was low. So I did wonder about anaemia but they let your HB go to 110 in pregnancy before doing anything.
Thanks again, I’m going to definitely pursue this further with the GP.
They can check for these too. Anemia should always be treated, but so should low levels too. Again, hang out on here often enough and you’ll soon learn.
Right now, hopefully everything is fine with a baby, but your own health is at risk and that’s no good for either of you.
Elevated CRP means you have inflammation in your body. Very common in autoimmune diseases. Also, FYI, a ferritin result would be be raised which is a false high when there is inflammation. So, always have both testers at the same time.
And, finally, a Ferriten result of 30 or under needs treatment irrespective of haemoglobin.
However if the GP says it’s ‘within normal range’, what can I do?
Do your research and advocate for yourself. You’ve made the first step in reaching out on here, and I am sure lots will be able to help. And as greygoose has mentioned, T4 should never be under range.
Low T4 means you are hypothyroid. In most people the TSH level wouid increase to above the reference range limit if T4 is low. I lived with low T4 and what appeared normal TSH for many years and was left undiagmosed and untreated because Dr's failed to understand that low T4 is hypothyroidism. TSH is a pituatory hormone and when the thyroid gland fails to make sufficient T4 then the pituatory gland should be sending lots of TSH to stimulate the thyroid gland, if your TSH isvt raised then it means your pituatory gland is not doing it's job correctly. I now see a private consultant Endocrinologist and he understood that low T4 With what appeared normal TSH was not good.. He treats me by measuring my T4 & T3 Levels. Please ask your Dr to consider pituatiry dysfunction. (hypopiturism) best wishes
Thyrotoxicity is when your FT4 and FT3 are wildly over-range! And they are more concerned about over-range than under-range, which is crazy! Especially if the patient is pregnant!
but not to worry as TSH normal
I despair, I really do. TSH is THE least important number. And - gets a bit complicated but - it's probably within the so-called 'normal' range (which is pretty meaningless in itself) because your FT3 is ok-ish. But, all sorts of warning bells should be ringing, here, and you do need full thyroid testing:
TSH
FT4
FT3
TPO antibodies
Tg antibodies
The FT4 should not be under-range at any time. That means there is some sort of problem and they should be looking to see what it is. TSH isn't even a thyroid hormone. (Don't want to bog you down with details at the moment, but there could be all sorts of reasons why the TSH is where it is, it doesn't automatically mean that the actual thyroid hormone - T4 and T3 - are 'normal'.)
Still, you're in the second trimestre now, is that correct? So, the baby has its own thyroid. But, now you have to think about you. Fatigue is a hypothyroid symptom and something should be done about it. You shouldn't have to continue your pregnancy in this state.
What time of day was the blood draw for this test? It does need to be done again, of course, but for the next test, make sure that the blood draw is done in the early morning, before breakfast. That could make a big difference to the TSH. And, don't accept them just testing the FT4, that is stupid. The three results - TSH, FT4, FT3 - are all interconnected and should be assessed in conjunction with one another.
It doesn’t make sense why they mentioned thyrotoxicity if mine is under and that means over surely.
What reasons could there be for the T4 being under?
I’m in the third trimester now (just). But was second trimester with 1st result of low T4.
It’s reassuring to know that baby has own thyroid at this point.
To be honest, because they initially said not to worry, I have just plodded on assuming this is pregnancy related tiredness, but now I’m starting to wonder.
Blood was taken at 9.20am.
I’ll ask for all the above to be checked, if they will! I’m not sure they’ll check it all again now though or if I’ll have to wait the 6 weeks?!
I wish it was immediately clear cut and I knew it was either hyper or hypo and be treated if needed. It seems the TSH is muddying the waters and I’m not knowledgeable enough to navigate it!
Trying to help with why they mentioned thyroxicity to you and it being OK, the TSH reference interval for the euthyroid (people with no problem) general population has been set to somewhere between 0.2 and 5. However some people will feel normal below and above this range. So when you get your TSH and range from them you can compare, are you at the bottom end or top end of the reference interval. Anything between bottom and top of range are what the GP will call ‘normal’. This is the biggest most annoying thing about testing for thyroid …. I feel absolutely blooming awful if my TSH is above 1, dreadful lie in bed or sit in a chair can’t even read dreadful, but apparently all ‘normal’.
So to actually feel well when hypothyroid (which is what your low FT4 suggests) I would need Levothyroxine to raise my FT4 which would also bring my TSH down (pituitary hormone signaling my dicky thyroid which isn’t listening).
However in pregnancy as mentioned above, the reference interval or range is different, I think she said TSH is not supposed to go above 2, so if you are ‘normal in the gen pop range you may not be normal in the pregnancy range, it may differ by trimester I don’t actually know and personally I’d get onto midwifery, antenatal nursing as well as GP and pop in and stand at reception while they print your results and ranges, accept nothing less, happy to wait, all the time in the world etc etc.
The thyrotocicity thing is likely to be because you were having palpitations, they would have a preconception you might have a LOWer than reference interval/range TSH, the test showed not, so they are saying it’s fine you are normal you aren’t thyrotoxic but maybe they’ve overlooked the fact that your FT4 is below range which is not ok. They’ve likely missed that you are probably hypothyroid AND pregnant which needs addressing.
Absolutely prioritise this, I was ignored after feeling dreadful after both pregnancies 21 and 19 year old babies now. Told I had post partum thyroiditis it would clear up, it didn’t I’ve dragged myself around for 20 years until a Polish locum spotted it when I was desperate and pleading for help.
Let us know how it goes, it’s time to get your mamma hustle on, you’ll be sprinting after a toddler in no time 🤗
Sorry you’ve had a struggle and felt awful for a long time.
You’re right, I’ve got to get onto this. My plan is to ring and request a copy of all results tomorrow and if they won’t email then I’ll have to pop to the surgery. I will talk to antenatal consultant tomorrow too. And book in to see/phone call with GP to ask for further testing. I’m not going to just accept this now, after all your replies.
Thank you to all with for the information. I’ll update.
hi Sunshinebright re ‘ My plan is to ring and request a copy of all results tomorrow and if they won’t email then I’ll have to pop to the surgery. I will talk to antenatal consultant tomorrow too. And book in to see/phone call with GP to ask for further testing. I’m not going to just accept this now, after all your replies.‘
Get all your blood results from doctors and contact the various departments but bring results here … there is great knowledge here combined and I would go so far as to say more than the doctors as you have observed first hand. I don’t want to be derogatory but sometimes they are happy to say normal this normal that while we are left crawling through mud … which can be so improved when treating and raising low levels of t4 t3 monitoring and treating low b12 low d low iron etc etc . It sometimes feels like if the doc sees the word normal on the result then all is well. In fact all is not well and we’re clinging on by our fingernails at the lowest end of ranges. Good luck
Oh, and one last thing, check the forum’s search option with the word ‘pregnancy’ and hopefully you will quickly learn what you need to know at this point. Keep posting questions, everyone will help 🫶🏽
The reference range for FT4 in pregnancy is lower, according to my local hospital (Brighton).
The normal range for FT4 is 11.1 - 22, 1st trimester 12.1 - 19.6, 2nd trim 9.6 - 17.0, 3rd trim 8.4 - 15.6. TSH and FT3 ranges are different, too. frontierpathology.nhs.uk/pu...
I’ve noticed these ranges vary across different hospitals and may be 1. Influenced by the equipment used and 2. Out of date. However, generally, accepted range doesn’t always correlate with the patient feeling well.
I have just read Dr Sarah Myhill’s book on ‘the underactive thyroid’ and she states that obstetricians like maternal TSH to be under 1.5. The lower the TSH , the healthier the baby- physically and mentally.
You really need to insist on knowing your test results . It’s not acceptable for them to hide things from you. Register with the practice so you can see everything online. Never leave an appointment without a print out of all your test results and an explanation of the results.
Maybe a good idea to do your own private thyroid test.
Hi just read everyone’s messages make sure you are testing FREE t4 and not just T4, also FREE t3 is more important that FREEt4 get your blood results for the TSH back but remember you are pregnant, your growing a baby. I would say get your Ferritin levels checked also as normally this is the cause of fatigue and stuck in the mud feeling during pregnancy, also vitamin D. Are you taking a Folic Acid if so a lot of women can not methylate it and if you can’t methylate it then it will make you feel quite unwell actually one of the main causes of natal depression as well. I would recommend Methylated folic acid as it’s already in the form the body needs to convert it to first far better quality.
Thank you all for you messages and information. I don’t have time to reply individually to everyone right now but wanted to update that I have requested a copy of the results. They will try to email, if not will leave printout at reception for me.
I have a phone call this morning with the GP to discuss all of this.
I plan to ask about further bloods and if not I’ve looked at medichecks and can have a blood sample taken through them at my local hospital so will go down that route if GP won’t do them.
Will update later, thanks again!
Interesting to note about the pregnancy reference ranges, maybe that’s why they aren’t concerned as technically I can go even lower in the third trimester.
Hi. Please note, each area has their own pregnancy trimester specific ranges (you can checks yours by checking your hospital labs pathology biochemistry tables if available). When they don’t they use standard pregnancy ranges (not sure what these are however). As for test, it’s definitely the FT4 and FT3 that needs testing as someone mentioned above.
The problem is I have this problem my t4 below range but tsh is within normal limit. I ask this question constantly but told that just below or above is OK. The thyroid stimulating hormone will start to rise if your thyroid t4 levels drop significantly. I was found after my last baby that I had an under active thyroid but took them ages to come to the diagnosis and I was quite unwell too. They didn't check levels 28 years ago.
I would advise you to question this as you are pregnant
Hi sunshinebright, glad to hear you will get copies of your results, that’s your right! I suffered from subacute thyroiditis at the beginning of pregnancy. At first I was really hyper, then had a few weeks of all normal and in my third trimester I had good tsh (well below 2) but free T4 slightly below reference range (which was indeed different during pregnancy) so my consultant obstetrician started me on levothyroxine. My problems started post pregnancy with the gp not really understanding my thyroid situation (I now have both bottom range tsh and bottom range free t4), but at least during pregnancy the maternity department was on it! Could you ask the midwife to check with a consultant obstetrician?
Hi hope you get things sorted last thing you need when pregnant is having the stress of dealing with patronistic numpties. Did you have thyroid issues before pregnancy, were you receiving treatment. Those on Levo typically would get an increase of meds in pregnancy which may be able to be reduced again later. Yes poor thyroid affects fertility , I tended not to have problems getting pregnant but staying pregnant was another story. The symptoms of palpitations , breathlessness , tiredness can be normal pregnancy but normal in the context of lungs having less room, blood volume increases so HB drop s, doesn't mean they shouldn't be exploring more fully the causes. Tiredness breathlessness feeling like walking through mud can can also indicate thyroid issues and or anaemia but CRP can cause raised ferritin and treatment for anaemia is usually based on ferritin below 30. Having a good healthy, not just in range HB lessens helps with fatigue, breathlessness and reduces risk of excessive bleeding at birth/post birth. Hope the appointment goes well and that you see someone who doesn't rely on the little asterisk next to blood results to be able to evaluate the result.
Thank you for all the replies, it is all useful information and your experiences are invaluable as I’m completely clueless in this area. I have never had thyroid problems before. I will respond to each later. But just wanted to update that results are-
T4-10.3
TSH-2.35
GP was nice but firmly assured me that they had spoken to an endocrinologist yesterday and that it is fine to leave it like this and test again in 6 weeks. She said there is no risk to baby. I asked about further testing but assured there is no need. She said that they would only treat with thyroxine if my TSH was 5 or above. She said they wouldn’t want to treat at this level as it may cause significant side effects which may cause harm to me and/or baby. I explained that I understood T4 should never go out of range and I would like to know exactly why this is. She said that it can happen in pregnancy and pregnancy is the reason.
The GP was keen to start me on iron supplements due to Hb-119. She seemed to think this is likely the cause of my symptoms.
So the plan she said is have thyroid retested in 6 weeks and iron retested in 8 weeks.
I’m not convinced this is correct based on all of the information I’ve read here, but I couldn’t really argue it any further. I am seeing the antenatal consultant this afternoon and will ask about the thyroid there.
Good your being started on iron supplements. Iron helps thyroid. Your TSH is in good range for pregnancy, and there are risks to starting treatment during pregnancy if not indicated.
I’m afraid there is even less information/guidelines on FT4 and ranges during pregnancy.
Hope you get in better and clearer answers with antenatal consultant, as I’m still not convinced FT4 should ever be under range.
Antenatal Dr not concerned either 🤷🏻♀️ she said they are concerned with TSH levels. However she did request another thyroid test which I had in the antenatal clinic today because she didn’t have a copy of the results on their screen. So that was that really. Not sure what else I can do. No one seems concerned. I think I’ll wait for these results and then book private bloods.
She also didn’t agree with GP about starting me on iron tablets as she said a hb of 119 in pregnancy is fine. But she did say I can take them as they won’t do any harm.
Hi....Please dont take iron when pregnant....do a google search on the side effects to the body........I was reading your post above and it sounds just like my daughter. Please note I am not a Doc..but just telling you what the doc said about my daughter....She is 29 years old and 26 weeks pregnant and her TSH is 0.46 and her T4 is also around 10..in the lower ref range...with the same reference ranges as you (she used Ampath)... We only had her TSH tested all the time and she was tired and sluggish all the time...then we did a full panel thyroid test and then saw that the circulating thyroid in the blood which is the T4 is at the bottom of the range and needs to be increased. I took her to a doc at Mediclinic and he upped her thyroid dose which was 200mg Euthyrox and he explained her levels are too low and upped her dose to 250mg...so it sounds just like you and you need to find a doc who will listen to you and up your dose...which is especially important when pregnant....low dose thyroid can cause lower IQ babies...She was also sluggish and tired a lot...we will have her thyroid tested again in 3 weeks to see if her T4 levels are rising....her anitbodies are also high
well lets see if they get their acts together, personally I would take the Iron, because blood volume increases by 40% in pregnancy and upto 60% by end of pregnancy but red cell volume is not increased as much, more blood volume but less HB, basically it is diluted. Hopefully breathlessness fatigue may improve. with iron , and help you feel better
Thank you, yes I’m going to take the iron for sure.
I still feel concerned about the T4 but at a loss of what else I can do if they are both saying it’s fine. My plan is to wait for these results to come back and then get a private test taken for more in depth assessment if they still aren’t concerned (which I doubt they will be because my last test was only on Monday! Can’t imagine the results will have changed!)
Thank you to everyone for all the help and advice.
I think they’re such a thing called central hypothyroidism that I’ve seen mentioned in the forum which is just based on T4. See bestpractice.bmj.com/topics... (take screen shots as you can only read once for free).
Symptoms of central hypothyroidism are similar to those of primary hypothyroidism (including fatigability, cold intolerance, weight gain, and depression), and may or may not be accompanied by symptoms of hypopituitarism, such as those of hypogonadism (i.e., decreased libido, infertility) and secondary adrenal insufficiency (i.e., weakness, nausea, vomiting).
Signs of central hypothyroidism on physical examination would also be similar to those of primary hypothyroidism and may include dry skin, hair loss, bradycardia, and delayed deep tendon reflexes.
Specific signs suggestive of a sellar or parasellar mass include papilloedema and bitemporal hemianopia.
Diagnostic evaluation of central hypothyroidism includes serum thyroid-stimulating hormone (TSH) and free thyroxine (T4) concentrations. In central hypothyroidism, free T4 is low and TSH may be low, normal, or minimally elevated. Magnetic resonance imaging may reveal a sellar or parasellar mass or infiltrative disorder.
Treatment of central hypothyroidism is by thyroid hormone replacement (levothyroxine).
Complications of treatment may include thyrotoxicosis and osteoporosis.
Definition
Hypothyroidism is a condition resulting from the deficiency of thyroid hormones, which leads to a generalised slowing of metabolic processes. Central hypothyroidism arises from an anatomical or functional disorder of the pituitary gland and/or the hypothalamus. This decreases thyroid-stimulating hormone secretion, leading in turn to decreased thyroid hormone synthesis and release.[1] Central hypothyroidism may be due to congenital, neoplastic, inflammatory, infiltrative, traumatic, or iatrogenic aetiologies.
Here it is pasted just in case. Last reviewed July 2023, so very up to date any wouldn’t suppose if the medical professionals you are dealing with are not aware of it. Good luck and I hope it helps.
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Bloods on NDT - Low T4
Bloods show low TSH AND T4 on NDT
Can anyone help with these test results please? TSH 2.36 Low end T4
TSH low the rest normal
