TSH 3.70 µIu/ml & FT4 0.97 ng/dl at 19 weeks of pregnency

[Gaurav1]

I have a question.

My wife is 19 week  pregnant on 18/05/2012.

She had her last menstruation on 06/01/2012.

Her TSH on 22/02/2012 is 6.42 µIu/ml

Her FT4 on 22/02/2012 is 1.13 ng/dl

Her TSH on 30/03/2012 is 1.55 µIu/ml

Her TSH on 13/04/2012 is 2.46 µIu/ml

Her FT4 on 13/04/2012 is 1.08 ng/dl

Her TSH on 11/05/2012 is 3.70 µIu/ml

Her FT4 on 11/05/2012 is 0.97 ng/dl


She is taking  Thyronorm 50 mg daily from 25/02/2012 without any break.

We ask our  gynaecologist about this rising TSH level, but he told that as she (my pregnant wife) had her TSH & FT4 level within normal range during 1st trimester , so no need to worry & no need to increase the dosage of thyroid medicine. Our gynaecologist  also told that since no symptoms  raise in my wife ‘s body so no need to increase the dosage of thyroid medicine

So my question is --

1) As the  TSH of my wife is raised to 3.70 µIu/ml & FT4 decrease to 0.97 ng/dl , where as in this forum it was told  by "Mark Lupo " that TSH Target for pregnancy is 0.3-2.0.  so does it have any impact on the baby & mother ?! Is there any need to increase the thyroid medicine dosage?

2) Since FT4 is decreasing to 0.97 ng/dl , so is there any need to worry ?

[Mark Lupo, M.D.]

pregnancy increases thyroid hormone demands.  Goal TSH is usually 0.3-2.0 during pregnancy.  The levels you post do not pose risk to mom/baby, but would consider increasing the dose to keep TSH in goal range.

[Gaurav1]

Thanks Sir