Thyroid issue while getting pregnant

Hi all,

I am 27 and I came to knw that i am hyperthyroid.Tsh levels were 5.8 at the time on conception and i was not on medication.

I am 5 week 4 days pregnant now. And i hv started thyroid medication at week 3 .

Will it cause any problems during my pregnancy.

My Tsh level is 3.8 right now and doc told me it shud b less than 3 during pregnancy.

Increased Thyroid results in brain issues that what i read somewhere.

Anyone with similar issues, please help me clear my doubts.