low TSH and Pregnant

[RH1975]

I am 5 weeks pregnant and i take Synthroid 112 mcg.  I recently found out that my T3 and T4 are normal but my TSH is very low (0.004).  Looking back to my test results, even back to oct of 2005, my TSH has always been low.  I currently live in East Africa where it is not very easy to get the right doctor for this things. Now that i am pregnant i am worried so i saw a specialist i could find who suggested i lower my dose to 100.  Since i can't find Synthroid here, again with an advice of a doctor i am skipping one dose a week.  I did a test after skipping just one and the test was still the same.  Today is my second week skipping a dose, i am planning to get a test done sometime next week to see if it will be different.  If skipping a dose helps my plan is to get the 100mcg as soon as i can and start taking one everyday.  Does having a Low TSH has any danger to my baby????  Please help me.

Thank you

[RH1975]

Thanks you Doctor,

I had a new blood work done on the 22nd, i did all T4,T3, TSH, Free T3 and Free T4 as well.  They are all in the normal range.  Except My TSH. But it looks like it is going towards the normal range.  I'm now at 0.400.  I will keep you updated with my changes.  I'll keep getting blood work done every 3 -4 weeks  so that i can adjust my dose as needed but i will keep you informed before doing anything.

Thank you

[Mark Lupo, M.D.]

It is fine to skip a dose per week if the dose needs to decrease, alternatively to take an extra tab or so per week if it needs to increase.

TSH is probably the best, but T4 can be monitored - there is debate about FT4 or total T4 being better....but Free T4 is in most guidelines still...

[RH1975]

Thank you so much.  I will keep a close look at my TSH, keep doing regular blood work done and go back to my original dose or maybe even increase it as needed.  

So is it ok to skip one dose a week then????  And also should i have free T4 done?

Thank you again.

[Mark Lupo, M.D.]

A low TSH with normal T4 and T3 is not uncommon with pregnancy and is safer than a high TSH.  With pregnancy the synthroid requirements increase by 25-40%, so watch carefully after this dose decrease and make sure the TSH does not go above 2.5.