Levo dose advice during IVF cycle - impact of HRT

[StormsPass]

Hello again 🙂

I’m wondering if anyone has any insight on the impact of HRT on Levo - Estrogen & Progesterone specifically which are the medications given during a Frozen Embryo Transfer cycle. NICE says there is anecdotal evidence of a moderate interaction between the medications.

The progesterone is taken vaginally and intravenously so not impacted in the gut but the estrogen is orally and a high dose of 6mg per day.

Below are my results. 1st test was at the start of the medication, 2nd result on the day of embryo transfer, 3rd result when I stopped the medication.

The TSH increase is quite substantial.

You’ll see I upped my dose to a flat 75 from 75 - 6 days / 50 - 1 day half way though but such a small change shouldn’t have made a positive difference.

Hopefully this post helps others as the IVF docs want our TSH below 2.5

Caveat - pls ignore my FT4 as I do take it before I test (naughty naughty)

Thank you as always 😀

[jimh111]

Not my subject but oestrogen increases the binding of thyroxine to proteins and so reduces the amount of free thyroxine which will push up TSH. So, with increased oestrogen you have the same TT4 but lower fT4 and hence higher TSH.

[StormsPass in reply to jimh111]

thanks Jimh yes I had read that also. I will have to speak to my clinic and show them the results to understand how much I should increase the dose during the taking of these meds. Then return to normal dose afterwards

[SlowDragon Administrator]

Are you testing correctly, early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

All three results show Ft3 is too low

Last two results shows you need dose increase

When were vitamin D, folate, ferritin and B12 last tested

[StormsPass in reply to SlowDragon]

Thank you Slow Dragon. I try to test consistently at 7am because I have to leave the house for work. But I do take my Levi before so I generally don’t pay too much attention to the FT4. I know I should not take my Levo but I have always done this so I am comparing consistent results.

I have had to test every 2 weeks ish for a long time to ensure my TSH is stable for IVF because I has a thyrtoxic episode where I was over medicated despite being on my normal dose. I think you call it a hyper storm

Vits were tested around 8 months ago

[SlowDragon Administrator]

Pregnancy guidelines

thyroiduk.org/having-a-baby/

NICE guidelines that if hypothyroid or subclinical you should see endocrinologist BEFORE TTC

cks.nice.org.uk/topics/hypo...

See pages 7&8

btf-thyroid.org/Handlers/Do...

Also here - dose increase in levothyroxine as soon as pregnancy test confirms conception

cuh.nhs.uk/patient-informat...

thyroidpharmacist.com/artic...

Low ferritin, low thyroid levels and miscarriage

preventmiscarriage.com/iron...

Low iron and hypothyroid

endocrineweb.com/news/thyro...

Folate and B12 and Neural tube defects and autism

healthunlocked.com/thyroidu...

ec.bioscientifica.com/view/...

[StormsPass in reply to SlowDragon]

Thank you for these links