Log in
Thyroid UK
93,532 members107,581 posts

Thyroid swings from under to over & IVF

Hello there

I’m looking for some advice on a new thyroid issue – I’ll try and summarise, but please let me know if you need more info.

Back in Oct 2014, blood tests before an operation for severe endometriosis showed slightly elevated TSH (5.78 and 8 on two respective tests). My consultant, who knew we were trying for a baby and needed IVF put me on 100mcg of thyroxine. The resulted in me losing a lot of weight very quickly and becoming overactive (TSH suppressed, FT4 =33.5). The consultant dropped my dose to 50mcg (TSH suppressed, FT4 =28.3) and then took me off thyroxine completely and whilst my TSH remain suppressed, my FT4 came into range (22.8).

As my results were in range, I undertook a round of IVF which was not successful, but lead to a high quality embryo being frozen. My IVF consultant is keen for me to use this frozen embryo, but my latest blood test showed a massive spike in TSH (>100) and my FT4 dropped to 3.0 – at this point I had been off the thyroxine for around 6 weeks. I had been feeling unwell, but thought this was due to the physical and emotional impact of IVF.

I have been put back on 50mcg of thyroxine, and have started to feel better.

My thyroid consultant (very experienced private London consultant) seems at a bit of a loss as to what is going on, describing my symptoms as unusual. He believes that my body is causing the swings from under to over active, hence why he is struggling to control the issue with drugs. He has previously said that my endometriosis (an immune issue) is not linked to my thyroid issue and really it’s just a waiting game. He hasn’t responded to my questions about Hashimoto's or whether I need a thyroid immunity test.

I’d be very grateful if someone can give me their thoughts on what is going on, and whether you think it would be worth getting a second opinion. For background, I’m 33 and until my fertility tests had not shown any adverse effects from either the thyroid or endometriosis. I work in London, and am willing to throw some money at this problem to help get to the bottom of it!

Many thanks

9 Replies

SparklyT, you can order a private thyroid panel including antibody tests from Blue Horizon and Genova via thyroiduk.org.uk/tuk/testin...

Autoimmune thyroid disease (Hashimoto's) can cause fluctuations in thyroid levels but suppressed TSH to TSH >100 in 6 weeks is extreme.

NICE recommends that TSH of women attempting to conceive or newly pregnant should be in the low-normal range 0.4-2.00 with FT4 in the top 75% of range. The risk of miscarriage is greatly increased when TSH is high.


1 like

This probably isn't useful, but I thought I'd pass it on anyway.

I had very severe endometriosis. I also have hypothyroidism and high cortisol. I discovered, quite by accident while searching the web, that there is a connection between endometriosis and high cortisol. There is also a connection between cortisol being out of range (low or high) and thyroid problems. Whether it is stress and pain from endometriosis that causes raised cortisol, I couldn't say. It could also be the other way around - that high cortisol causes endometriosis - I'm not a scientist, so again I couldn't say.





This is very helpful, thanks for taking the time to post. I didn't realise that there could be a link with high cortisol. I presume you are just trying to manage your stress in the usual way?

I wonder if the stress I was feeling through my IVF has in some way affected my TSH.


Trying to lower high cortisol is very difficult, or at least I have found it so. The only advice I would have for someone trying to get pregnant is to remove as many causes of stress as you can, and I know how hard that is!

One cause of stress on the body is being low in minerals and vitamins. In your shoes I would try to find out your levels of ferritin, folate, vitamin B12, vitamin D, a full iron panel - serum iron, TIBC (Total Iron Binding Capacity), transferrin saturation - and also get a full blood count. Post the results in a new question on here, and people can make suggestions about what needs fixing. People with thyroid problems often have deficiencies or low levels.

If money isn't too much of an issue, then you could also get zinc, copper and selenium. And you could also test iodine, which is best tested with a urine test, not a blood test.

The full thyroid testing that Clutter mentioned above would be useful.

For all your blood tests, make sure you do them as early as possible in the morning (by 9am at the latest is preferable), having fasted for 12 hours beforehand (except for water which you can drink freely). I don't know the conditions required for a urine iodine test, I've never had one.

I've had life-long insomnia which I suspect has been caused by high cortisol. Fixing my minerals and vitamins has made a big difference to this, and I now sleep far better than I have done since I was a young child. And getting good sleep is also good for adrenal health. The issue is not just getting minerals and vitamins into the reference range, they need to be in the optimal range, and that differs depending on the substance.

If you have problems with insomnia, this might be helpful :


Hope some of this is useful.

Good luck!


If you want suggestions on reliable places to get private testing done, please ask.


Yes please, I'd be grateful for some recommendations via PM as it seems a minefield out there! Many thanks


There is no need to do it privately, we are allowed to discuss testing companies. :)

The main website of Thyroid UK has a good page on private testing, with lots of links for you to follow.


Genova Diagnostics

This company does adrenal stress profiles which are very popular for giving people an idea of adrenal health and cortisol output. It is a saliva test.


I've also used their Thyroid Plus test, but I think Blue Horizon has better value tests now :


Blue Horizon Medicals

Just for info, the Thyroid UK link given first in this post has one website missing (that I know of) for Blue Horizon Medicals :


Please note this is not the same as :


although both the above sites are Blue Horizon sites.

Please note that different tests and combinations of tests are available at each of the six Blue Horizons websites, and prices differ too, so check each one that might apply very carefully. Phlebotomy is included for some sites, and is not necessary for the finger prick testing. Some sites require you to find your own phlebotomist for taking blood. Some of the websites have special offers on each month, so check them out. When I first used Blue Horizon, I registered with the site I was using and doing so got me another 5% off the price. I don't know if this still applies.

I have used the Comprehensive Plus V test from the Spire website, which has always been very good value for money :


Vitamin D

I've never bought a separate Vitamin D test, I have always paid for combinations of tests that include it. But if you wanted a separate test then you could use the City Assays link on the Thyroid UK page.

Hope this gets you started. :)


It certainly does! Thanks very much for taking the time to send me this, I'll start investigating all the options this weekend.


I would definitely get your TPO tested and your FT3.

Your thyroid and adrenals areinkrd and work closely together (when one is malfunctioning the other will try to compensate and eventually suffer as well)

When on IVF you take a number of medications some that stop all of your sex hormone production then some that massively stimulate your egg production. Your adrenal glands are the glands that produce a fair bit of your sex hormones so any IVF treatment has quite an impact on those.

I think it would be a good idea to have a 24hr adrenal saliva test (from Genova) to see if the adrenals are hampering how well you feel on thyroid medication

1 like

You may also like...