High TSH 5 weeks pregnant

[AshleyM25]

Hi,

I just found out the my TSH is 7.1 at 4.5 weeks pregnant. I had it tested 2 months ago and it was .87  I've been taking 75 levothyroxine. Am I going to miscarry? They told me to up my dose to 125.
My Free T4 is 1.09  (range .85-1.38) I don't know my free 3 but am on progesterone suppositories so my progesterone has to be ok. I am a mess and would love some help. I go to meet with an endocrinologist next week. What should I ask him?

[Barb135]

LOL - you're quite welcome... there's a lot more you'll need to learn, but you'll get it as you go along.  

First off, there are 2 antibody tests for Hashimoto's, so make sure they did them both in order to determine that you don't have it. The tests are Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb).  Many times doctors will only to one of the tests, but since both of them are markers for Hashimoto's, you'll be misdiagnosed if they don't do them both...

Secondly, in order to explain the levothyroxine, I'll briefly explain the way the thyroid works, then it will be easier to understand...

The thyroid produces 2 main hormones - T4 and T3, but mostly T4.  Of the T4 that's produced, most is bound by protein and can't be used.  That's why test "Free T4" because we're testing the portion that's not bound.  Free T4 isn't used directly by our cells; it must be converted to T3 prior to use.

Free T3 is the hormone that used by nearly every cell in our body.   Like T4, most of the T3 in our blood is bound by protein and can't be used.  Again, we test the "Free T3" so we know how much is unbound and available for use.  

When our thyroid doesn't work well, we typically, prescribed levothyroxine as a replacement for the hormones our body isn't making.  It's assumed that our body will automatically convert the levothyroxine (T4) to the usable T3 that we need.  For many, that works and we do just fine.  For many others, there's a problem with the conversion process and we don't do just fine... In this case, we have to add a separate source of T3.   This is the T3 pill to which you were referring.

Not everyone needs this extra source of T3... This is why it's so important to have Free T3 tested every time you have blood work - to make sure your body is adequately converting the T4 (levothyroxine) to T3.  If you're adequately converting, but still having hypothyroid symptoms, there are things going on.  We can address that later if need be.  I just want you to understand how the medication works, to begin with...

Thyroid blood work should be done monthly so that adjustments can be made in a timely manner. throughout your pregnancy.

[AshleyM25]

You are so great thank you!! I am writing down everything to ask him. The nurse at my infertility office did say that I was negative for antibodies so I assume that I don't have Hashi? But unsure of course I am going to ask for new tests of everything. Does the levothyroxine take care of the Free T4 ? I know theres a different pill for Free T3 right? This is confusing but you are helping so much. At least I will know a bit about what I am talking about when I go to meet with the Endo. Aldo, how often should I request blood work throughout pregnancy? 2 or 4 weeks?
Thanks SO much!!

[Barb135]

First of all, you need to understand that TSH is not going to cause a miscarriage... It's the thyroid hormones that are important, not the TSH, which is a pituitary hormone not at thyroid hormone.  

Thyroid hormones are necessary for the growth and development of a fetus, so it will be necessary to get your levels high enough to sustain, both, you and the fetus until its own thyroid gland kicks and begins producing hormones.

Your Free T4 is at 45% of its range, so although it's not adequate, neither is it "horrible".  The problem is that your doctor didn't order the most important test, which is the Free T3.  That's the first thing you need to ask the endo when you see her/him next week.

In my opinion, increasing your medication from 75 mcg all the way to 125 might be too much.  You could go to 88 mcg or 100 mcg, then increase after a few weeks if need be.  Talk to the endo about that, also...

Do you know if you have Hashimoto's?  Have you ever been tested for the antibodies?  If not, you should ask the endo to test those because if you have Hashimoto's, you'll need to adjust your hormone dosage periodically to keep up with destruction of your thyroid gland, even after your baby is born.

In addition, do you know what your Vitamin B-12, D and ferritin levels are?  If not, you should try to get those tested also.