Thank you for submitting your query.
The normal TSH level
during third trimester is between 0.43 - 2.78 and your wife has absolutely normal values. You need not worry about this. It is indeed true that low thyroid
hormones affect the fetal brain and cause mental retardation. There is nothing to be concerned about right now. Just take her for regular follow-up as directed by your Doctor.
Vertical position on a ultrasound
scan suggests that baby is in upright position where in the fetal head is directed towards the head of the mother. Hope this answers your query.