What are the risks to an unborn baby in pregnancy if you have hypothyroidism?

I am 2 months pregnant with baby #1 and recently found out that I have hypothyroidism. My doc says it’s okay to take the meds she prescribed w little affect on the baby…but this is the same hospital that told my Grandpa he had bronchitis for a month-he died 2 months later of lung cancer. Is my doc right?