My endo says synthroid is safe to take during pregnancy and told me I must take it throughout pregnancy. My endo has been keeping my TSH at 0.5 while TTC and during pregnancy. I must say this level is the best I have felt. I do not feel all that well with my TSH above 3.5.
The thyroid gland controls a lot of your body especially growth. Infertility is a common symptom of hypothyroidism. If by some weird chance you get pregnant with an underactive thyroid, you run the risk of your baby having growth and mental retardation,heart defects,etc...Your level of 3.0 is not that high, but if TTC my endo says to keep TSH 1-2. I would check with your doctor. Hope this was helpful.

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