Good Day! Unfortunately Hypothyroidism while pregnant can be potentially dangerous for the developing baby as an inadequate level of the hormone may interfere with the baby s metabolism. Metabolism is extremely important for growth and development. The very good news however is that historically, Levothyroxine otherwise known as Synthroid, a first line treatment for Hypothyroidism, has been proven safe in pregnancy time and time again. It is extremely useful, and yields very positive results based upon my experiences. I would speak to your PCP and or OBGYN and mention what we have discussed. Perhaps a switch from Thyrox to these medications will suffice? If not I suggest you speak of other options for treatment. They are out there, and even with pregnancy, can be treated safely and tolerably. I wish you all the best.