Recurrent miscarriages and underactive thyroid

[Bananacake1]

Hi all, I'm currently going through my third early miscarriage. I would be grateful for thoughts on my latest blood results and treatment options going forward.

27/02/2025:

CRP HS: 0.44 mg/L (Range < 3)

Ferritin: 73 ug/L

Vitamin B12 - Active: 149.0 pmol/L (Range > 37.5)*

Vitamin D: 89 nmol/L (50-250nmol, I believe optimal for TTC is 100-150?)

TSH: 2.550 mlU/L (Range: 0.27 - 4.2)

Free T3: 3.9 pmol/L (Range: 3.1 - 6.8)

Free Thyroxine: 18.5 pmol/L (Range: 12 - 22)

Thyroglobulin Antibodies: 297.0 kIU/L (0 - 115)

Thyroid Peroxidase Antibodies: 97.2 KIU/L (0 - 34)

Homocystein (fasting) via TDL: 5.81 umol/L (4.4-13.6)

*I'm confused about ranges relating to B12 and would be grateful for advice.

Hormone profile has been tested and no abnormal results. Thrombophila / APLS screen also came back as normal. Karyotype (chromosomes) for me and my partner came back as normal.

Up until today, I was taking 75mg Levothyroxine (after positive pregnancy test I did increase this to 100mg until I realised I was miscarrying). I have seen a fertility specialist who has recommended alternate daily dose of 75/100mg to reduce TSH, without hopefully going above 20pmol/L for Free thyroxine (T4). I have also seen a Thyroid specialist GP who had advised considering T3 or NDT in the future as it is likely my body is poor at converting T4 into T3, however she was cautious change anything now while I am actively TTC.

I was also taking 150mg Aspirin from day 14 of cycle for the last pregnancy, as well as Cyclogest (Progesterone) from the positive pregnancy test. I am also taking supplements, which include Zinc, Selenium 200mg, Iron, Vitamin D, Methylfolate 5mg (due to MTHFR). I am now doubling my Vitamin D dose to increase into optimal fertility range. I follow a Gluten free diet.

The plan going forward is that I will have a uterine scan. I am also considering whether it would be helpful for my partner to have a sperm analysis, DNA fragmentation analysis, despite not having difficulty conceiving up until now. Once I am TTC again, I will be taking Aspirin 150mg, Heparin, and Cyclogest (Progesterone) from day 14 of cycle.

I would be grateful for your thoughts generally, and in particular on investigations done and any other investigations or medication/treatment that I can consider

Thank you all x

[Bananacake1]

To add, I have also been looking into the (d)EFT testing for natural killer cells in the Implantation clinic in The University of Warwick. Is this the only option for testing Natural Killer cells, or are there other options such as blood tests only that can test for this?

We are hoping to try everything when we next TTC as the losses are so heartbreaking. I have asked my fertility consultant about steroids however he was not supportive of trialling this due to side effects to fetus.

[Arlie123]

hi, so sorry for your losses it’s so heartbreaking. I think you will get better input if you post these results over on the thyroid board. But you’re under medicated - your TSH is too high considering you’re on medication. You could maybe go up in levo a little more but the real issue is your low t3. Amazing that your gp said that re t3 as usually they are clueless. I would push for it if you can as it will be harder to get when pregnant and you are in dire need based on those labs. You might need to go private to get it. Your ferritin also looks low - improving vits might help with conversion a bit.

I also don’t know why your consultant would say prednisone can harm the foetus - it’s used regularly in IVF - I’m 10 weeks pregnant and am on 25mcg - lots and lots of other people doing ivf are on it too.

Have you done tests for cytokines, microbiome etc? I think your thyroid is the main issue but might be worth looking at. Have a look at fertilysis for testing - but make sure you consultant would interpret them. The test I did via my clinic for NKC and cytokines (not the fertilysis one) was about £1k so not cheap but worth it. Sending lots of hugs.

[Arlie123 in reply to Arlie123]

Might also be worth considering more progesterone than just cyclogest. Progesterone is oil eg lubion as well. You might absorb this better. Does your clinic test your progesterone levels?

[Endofitall]

I’m sorry you’ve had to go through this. Have you seen a dedicated recurrent miscarriage specialist?

it sounds like you’re doing a great job to cover all bases.

Very sensible to get sperm dna frag done too given your recurrent losses. It’s not just about conceiving.

I take Ovum which has a higher dose of vitamin D. If you take supplements with B12 in the couple of weeks before a test that will often throw off the results on the B12 test in a way they don’t for things like vitamin D.

I agree that optimising your thyroid is priority. GPs hands are usually tied to only prescribe NHS/NICE approved levothyroxine but at present it looks like you could get your TSH down with increasing your dose.

As Arlie mentions, checking progesterone level in early pregnancy is important if they haven’t already.

Seeing the Warwick clinic with Professor Quenby/Brosens to consider the endometrial biopsy may just help you get your consultant to consider steroids for you (being nhs research clinic they are well known and respected). There are dedicated reproductive immunologists in the UK but the cost is higher. Fertilysis is useful as mentioned above.

Have you had a hysteroscopy? This is something else to consider.

Best of luck with it all