Pregnant - Normal TSH and FT3 But Low T4

[sophieblue]

I am 20 weeks pregnant and currently taking 1 grain of armour thyroid (which I have been on for over 20+ years and have done well on - I had a short spell on levo and had terrible hypo symptoms).  I had a thyroid panel at around 6 weeks and test results were all normal.  I went back in for another test since I've been feeling tired and getting headaches (similar to when hypo) and concerned over the recent reformulation of armour.   My TSH came back as 1.31 up from 0.60 at the 6 week test.  My FT3 was 3.1 (sorry I don't have the reference range but it was within the normal range) but the FT4 was 0.54 and the nurse said the low end of the reference range was 0.58.  She said since I was only slightly out of range that she didn't think anything needed to change.  I'm a little worried with the T4 being low - I know the studies on hypo and pregnancy all track TSH but I thought there were some smaller ones that said a low T4 is concerning for the fetus.  I currently have a 16mth old child that has some slight verbal delays so I'm sensitive to this.  I started taking the reformulated Armour about 8 weeks ago.  Do you think I need to talk with my OB about increasing my dose of Armour?

[Super_sally888]

Hi,

during pregnancy the figure to watch is FT4.  The FT4 should be maintained in the top 1/3 of the range.  

You do need an increase in thryoid meds based on this panel.

MOnitoring for thyroid during pregnancy should be monthly.  With adjustments made monthly to keep FT4 high normal.

It is normal during pregnancy to have to increase meds by 30 - 50%.  This is important for your welbing and the baby's development.

However, you levels are not terrible. So it is not likely that the baby is harmed, just that you do need to increase.

I am hypothryoid and now have a beautiful 6 mo baby.

[laura1967]

Most people that are on a optimum level of armour usually show close to or hyper tsh level. Free T4 should be at least mid normal range and free t3 should be high normal range.
Sounds like you need an increase....especially by looking at your numbers.  :)