I Am 25w Pregnant And I Have Been Seen By

I am 25w pregnant and I have been seen by a high risk doctor due to my age. At my first visit, the doctor noticed one side of my neck was slighly enlarged so he ordered a blood test to check my thyroid. Since the result came back with 0.37 (I guess it was tsh?), the doctor did not put me on any medication. With my second blood test 4 weeks later, the level however dropped to 0.19, so I started Methimazole 5mg 3x/day. The doctor didn't think I need to be seen by an endo specialist. I have been taking Methimazole for 2 days but I am so worried that the medicine might harm my baby and something might happen to him due to my low tsh level.