Does taking thyroid medication throughout pregnancy till delivery affect baby like delay in speech? I had hypothyroid and had taken medicine from the start of first trimester and subsequently got into normal range upon further medicine when checked after second blood test. But was advised to take till delivery with doses reduced. I am worried as my son is three years old and speaks less and is interested to learn alphabets then trying to communicate. I am planning for second baby so I am feeling depressed if my second child also will be of same because of my thyroid disease