Does HRT affect TSH levels?

[TooManyTablets]

Hi, I've recently had a review blood test to check my TSH levels and it has raised significantly since my last test. I've started taking HRT and thought I'd read somewhere that this can change how much levothyroxine you will need. I'm currently taking 75mcg Levothyroxine (teva)

I was also baffled that on my blood test results it said no further action needed! I've made another doctors appointment to see what I can find out but I thought I'd better ask you clever lot beforehand.

My blood test results:

30th December 2024

TSH: 6.2 mu/L [0.3-4.2)

T4: 15.5 pmol/L [10.0-22.0]

27th September 2024

TSH: 0.16 mu/L

T4: 18.6 pmol/L

I started HRT about 20th October 2024, estradiol 1.53mg/dose transdermal spray and Gepretix 100mg capsules.

I'm very careful with the timing of my medication, I stick to a regular time to take them, and I make sure I leave at least an hour after taking Levothyroxine before eating and drinking. I also take my vitamins/supplements about four hours after Levothyroxine.

I rarely drink alcohol and I'm trying to eat healthier. I've still got to try being totally gluten free but I have reduced my gluten consumption for the time being.

I've also noticed that since starting HRT I've had slightly less brain fog and although tired not as exhausted as before. However, now I feel like I'm returning to how I felt before I started HRT.

Could it be the HRT has changed my Levothyroxine requirements? Is there anything else that could have caused raised TSH levels?

Thank you in advance for your thoughts and advice, I really appreciate it! Xxx

[SlowDragon Administrator]

yes it does frequently change how much levothyroxine you need

Usually an increase

But your own thyroid could simply have become more damaged and now ready for next increase

75mcg was low dose unless very petite

Free T4 (fT4) 15.5 pmol/L (10 - 22) 

Ft4 only 45.8% through range

Was test done early morning and last dose Levo 24 hours before test

Do you always get same brand levothyroxine at each prescription

Request 25mcg dose increase and retest in 2-3 months

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

What vitamin supplements are you taking

[TooManyTablets in reply to SlowDragon]

Thank you for your help.

My blood test was done first thing in the morning and 24 hours after my last Levothyroxine tablet.

I always have the same brand of Levothyroxine.

I think it's been a while since my last test for vitamin d, b 12, folate and ferritin but I'll check and request more tests.

I'm currently taking oral spray vitamins d/k2, b complex, spa tone iron sachets, vitamin c, selenium, magnesium glycinate malate and citrate (three in one capsule), turmeric capsules and cod liver oil.

[Buddy195 Administrator]

Many members report needing slightly more Levo when on HRT. I would certainly ask for an increase. I’m a fan of low and slow increases - so if an additional 25mcg prescribed, I would start with 12.5mcg and increase again once well tolerated (others however are fine with an increase of 25mcg in one go). Do ask for levels to be retested 6-8 weeks after being on a new dose. Also worth asking for key thyroid vitamins to be rechecked (ferritin, folate, B12 and vit D).

[TooManyTablets in reply to Buddy195]

Thank you for your help.

I think it's been a while since tests for vitamins but I'll check and request to get them done again.

[TaraJR]

People often find they needed more thyroxine after starting HRT, myself included.

But your TSH level does show a big change. You take a B complex - does it include Biotin B7? If so, how long before the test did you stop taking the B complex?

[TooManyTablets]

Thank you for your help.I stopped taking my vitamin b complex about 2 weeks before my blood test as it does contain biotin (b7).