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.