FAQ: What causes higher TSH levels during pregnancy?


Question: I am about 3 months pregnant and TSH levels have skyrocketed.  I have read on your website that TSH levels shouldn’t get above 5.0 mIU/L.  Mine are over 45 mIU/L!  That seems scary to me.  Should I be concerned about my baby or my own health at this point?

Answer: As long as you are under the care of a knowledgeable and competent medical professional, everything should be fine.  It is quite common for your TSH levels (as well as T3 and T4 levels) to be greatly affected by pregnancy.

You see, when you are pregnant certain hormonal changes occur in the body which can cause imbalances in some of the other hormonal systems in the body.

For example, the placenta (the protective sheath for the fetus) can product a hormone called human chorionic gonadotropin (or hCG) and estrogen.  Both of these hormones can cause the thyroid to go into overdrive and actually cause the thyroid to product MORE thyroid hormone.  This can cause TSH levels to go down.

In some cases, however, hormones released into the bloodstream during pregnancy can have the reverse affect.  These newly-introduced chemicals can cause T3 and T4 levels to plummet… and this, in turn, causes TSH levels to skyrocket.

In either case, you should seek treatment by someone who is aware of these hormonal interactions in the endocrine system.  You may need to be put on a semi-low (25 mcg) of Thyroxine and then ramped up slowly to a higher dosage.

4 Responses to FAQ: What causes higher TSH levels during pregnancy?

  1. Hana

    What happens if tsh is 150

  2. T.Naga Lakshmi

    I am 45 days pregnant . I TSH report showed the result at 6.38 uIU/mL. I their any risk involved.

    Case History:

    I have 6 years Boy who is suffring with Hyperactive.(ADHD)

    Already had 2 miscarriage

    can you guide me

  3. Linda

    My thyroid has been removed and obviously I have regular TSH checks for the level of thyroxine I take every day. In Septmber my level was 2.48 – today it has risen to 6.78 way above what is considered to be normal. I really don’t understand whether this rise means I should take a lower dose or higher dose of thyroxine. Can you help please.

  4. d

    I am 11 months pregnant n my TSH is 0.01 is tht a cause of concern for me or baby?