Mild hyperthyroidism treatment? Impact on IVF / conceiving?

[Babymagic37]

Hi all,

I’ve had some test results back:

T3 - 7 pmol/L (3.10-6.80)

T4 - 19.8 pmol/L (12.00 - 22.00)

TPO <15 iu/ml (0.00-34.00)

TSH <0.01 miu/L (0.27-4.20)

The GP said I’ve got “mild hyperthyroidism”. Up until August this year my thyroid has never played up, the levels have always been within range. I’ve had a sore throat and ear ache for about 6 months - maybe it’s related? I also suffered an early pregnancy loss in July which may have impacted my thyroid.

Could anyone tell me what I can expect in terms of treatment for this?

I was am due to start IVF next month - will treatment interfere with conceiving?

Any advice would be much appreciated x x

[PurpleNails Administrator]

You need TG antibodies tested even though TPO antibodies negative.  

The FT3 is very fractionally over range , this is what’s causing the TSH to drop.

Is the function being rechecked soon?   

Have you been given endocrinology referral? 

It’s a little soon to look at treating with an antithyroid, but if level rise further they may suggest you start a medication to control them & find cause of hyper levels.  

Hopefully treatment won’t be necessary and levels do fall back into range.  If antithyroid are suggested it maybe the case you’ll be advised to delay IVF until levels under control.  I’m Sorry if that the case & for your loss last July.

In early stages of Hashimoto’s (autoimmune thyroiditis) the Immune system attacks thyroid & damaged cell release hormone store causing a hormone rise.  This occurs in transient fluctuations but ultimately the damage gradually lead to low function & levels. 

Usually there is presence of TPO antibodies (these are the immmune system ‘cleaning up’ the thyroid debris which aren’t normally outside the thyroid) but they aren’t always detected.  

So monitoring is key.  You’re checking for a downward trend as much as an upward trend.A continuous increase can also be caused by an autoimmune condition stimulating the thyroid (Graves).

If FT4 & FT3 becomes higher doctors must determine cause.

TSI or TRab antibodies confirm Graves.  

Both hashis & graves can cause sore throat.  

I have similar results about 5 years before I was treated for a toxic nodule.  It was missed, I wasn’t treated.  

We don’t know what affect having high FT4 & FT3 has on fertility and pregnancy but it is known low FT4 & FT3 (which often cause higher TSH) does affect fertility & better levels are necessary to support pregnancy.  

[Babymagic37 in reply to PurpleNails]

Hi PurpleNails, thank you so much for your input, its so helpful. I am completely inexperienced when it comes to any of this. Like I say, my thyroid has always been fine until very recently.

When you say TG antibodies - is that thyroglobulin antibodies? What level would I want to see regarding this?

Do you mean a continuous increase in T3 and T4 may suggest an autoimmune condition?

The doctor is speaking to an endocrinologist for advice and getting back to me. I know an untreated thyroid can make conceiving difficult but I was hoping if I was on medication it may still mean I can continue with IVF. It's all so daunting 😞 x x

[PurpleNails Administrator in reply to Babymagic37]

Yes TGab is Thyroglobulin antibodies.

These are the common antibodies which are tested:

TPOab (Thyroid Peroxidase antibodies)

TGab (Thyroglobulin antibodies) 

TSI (Thyroid-Stimulating Immunoglobulin)

TRab (TSH receptor antibodies - measures stimulating, neural & blocking antibodies)

TPO & TG are often positive in those with Hashimoto’s, but also often present with Graves.

TSI & TRab are biomarkers for Graves.  

TSH (thyroid stimulating hormone) is a pituitary hormone - it signals thyroid to increase / decrease depending on where the thyroid hormones are.  If thyroid hormones are higt [FT4 free thyroxine & FT3 free triiodothyronine] it drops. 

 TSH would increase if levels low and need more hormone.  It best the test the Free (available to use) levels not the total level.  

Doctors often go solely by TSH and conclude under = hyper.  over = hypo in range acceptable. But it not quite that straightforward & simplistic.

The TSH can respond slowly & doesn’t alway reflect thyroid levels.   The range is wider than what many say is “normal” & as we are all different often many do not have a baseline to say what their normal is. 

If you have historical records then that’s helpful as you can compare.

Hopefully this is some temporary blip & it resolves.  

[Babymagic37 in reply to PurpleNails]

Thank you so much for your response. So I had the TGab tested last year and the result was 11.3 iu/mL (0-115). Does that mean I am positive for TG antibodies? I'm just confused as I had a numerical result as opposed to a "positive or negative" result. If that makes sense!

[PurpleNails Administrator in reply to Babymagic37]

no that’s a negative result, 0-115 or under <115 is the expected limit. over this level is higher than healthy & therefore positive.

[Babymagic37 in reply to PurpleNails]

ahhhhhh that makes sense - thank you! So anything over the range is a positive. This is all mind blowing stuff....thank goodness for this forum and people like you!! 🙏

[PurpleNails Administrator in reply to Babymagic37]

with antibodies there’s a limit range - but most other blood test results have a lower normal to upper normal range.

[SlowDragon Administrator]

ESSENTIAL to also test vitamin D, folate, ferritin and B12

Have you had these tested

[Babymagic37 in reply to SlowDragon]

Hi SlowDragon,

Yes I've had these tested:

Folate = >20 ug/L (2.8 - 15)

Vit B12 = 700ng/L (180 - 650)

Ferritin = 64ug/L (13-150)

It also says 'Total 25hydroxy vitamin D' = 98nmol/L (>50 is sufficient for almost whole population) so I'm guessing this one is ok.

What do those results tell you? TIA xx

[SlowDragon Administrator in reply to Babymagic37]

vitamin levels are good

 I also suffered an early pregnancy loss in July which may have impacted my thyroid.

Yes possibly it could have

Suggest you retest again in another 6-8 weeks