Confused after latest blood test

[ConsBananaHam]

Hi everyone

For some background, I had a total thyroidectomy 3yrs ago and am ~7mths pregnant.

I see a Bupa endo, who when I’m not pregnant prescribes me Armour because my conversion from FT4>FT3 seems bad, and I definitely feel better on that, but while I’m pregnant he likes me to be on just levo, which I’ve been on now for 8 months.

My latest blood results this week are below:

TSH 0.25 (normal = 0.27-4.2)

FT4 15.3 (normal = 12.0-22.0)

FT3 3.1 (normal = 3.1-6.8)

My current dose is 125mcg Levo and he wants me to decrease to 125mcg Levo Mon-Fri and 100mcg Levo Sat-Sun because my TSH is low.

My concern with lowering my dose is that my FT3 is already right at the bottom of the normal range so surely lowering my dose will make that too low?

I’ve always felt that my FT3 was the most important number and I’ve felt my best when it’s been around 5, but he says the TSH is the most important one.

My TSH has always been too low and I don’t understand why as my FT4 and FT3 are always mid-low range (aside from if I’m on Armour and can get my FT3 around 4-5 but my FT4 is still 14ish). I also don’t understand how my TSH can look like I’m being overdosed but my FT4 and FT3 still be so low?

I don’t trust my endo’s judgement anymore to be honest and feel so rubbish right now, the thought of lowering my FT3 and me feeling even worse really upsets me.

I will start doing my own reading but any advice would be really appreciated thank you!

[greygoose]

Looks like your pituitary is a bit on the slow side, and that's why your TSH is lower than would be expected with the level of your Frees.

I'm not medically trained, but I often wonder if some endos are! If it were me, I would say it was time to go back onto NDT. The reason for taking levo when you're pregnant is that it is T4 that crosses the blood/placenta barrier in the early days. At 7 months, I think I'm right in saying that the baby will now have it's own thyroid and no-longer be reliant on hormone from mother. But, I also think I'm right in saying that if the mother has low thyroid hormones, she will start to take them from the baby.

I don't really think your endo is fit for purpose. The last thing he should be worrying about it your TSH. If you were taking NDT, you wouldn't even need TSH. And, although it's the T4 that crosses the blood/placenta barrier, so you obviously need T4, that's no reason why you shouldn't be taking T3 along with it. Especially as your endo isn't even prepared to give you a high enough dose of levo. You need to stay healthy, too. And TSH helps neither you nor the baby, it isn't a thyroid hormone.

I think, if it were me, I would be having serious words with this endo, no only insisting that he doesn't lower my already too low dose, but that he puts me back on NDT right now.

[SlowDragon Administrator]

Essential to have good vitamin levels, especially as you are pregnant

Have vitamin D, folate, ferritin and B12 been regularly tested?

These are often too low when hypothyroid and we frequently need to supplement to maintain optimal levels

Presumably you have be taking some pre-natal vitamins?

For full Thyroid evaluation you need TSH, FT4 and FT3 tested. Also important to test vitamin D, folate, ferritin and B12

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw).

If/when also on T3, or NDT eg Armour- make sure to take last dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

Is this how you do your tests?

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies or all vitamins

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

TSH is almost always suppressed on any NDT or T3

FT4 is often low when on NDT

Your current results show very low FT3 and FT4. Personally I would increase Levothyroxine by 25mcg or ask to go back on Armour

On just Levothyroxine many patients need very high FT4 and suppressed TSH in order to have high enough FT3

.....FT4 at least around 19-20, if not higher

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.

In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.

Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor

 please email Dionne at

[e-mail]

Professor Toft recent article saying, T3 may be necessary for many otherwise we need high FT4 and suppressed TSH

rcpe.ac.uk/sites/default/fi...

Research shows 20% Patients with no thyroid can not regain full health on just Levothyroxine

ncbi.nlm.nih.gov/pmc/articl...

Treating hypothyroidism by TSH is useless

pdfs.semanticscholar.org/b2...