Hello and thank you for asking on HCM!
I read carefully your concerns.
In the third trimester of
pregnancy the upper normal limit of
TSH is considered 3.0 mUi/ml, (differes from the normal population).
So 5.1 is a bit high and she should continue the treatment with levothryoxine.
Rather it will affect the baby or not, we can't be sure for that, but we can say that it slightly increased.
All what we can do now is to start the treatment and check the TSH after 4 weeks to see if the dose is appropriate.
Usually
hypothyroidism caused by Hashimoto
thyroiditis is a chronic illness and she should take the treatment in order to substitute a hormone that is no longer produced by the thyroid gland. In this consists the treatment.
I can say that if she takes the pills regularly and does the check up as suggested there is no side effect or point to get worried.
Hope i was clear and helpful.
Kind regards,
Dr.Mirjeta