Patient :I'm pregnant and in my 5th week. Thryoid test showed that my TSH IS 3.0, free t4 1.4, T3 - 1.12 and i'm currently using 25mcg syntheroid as my previous TSH levels is 4.7. Do i have to increase my dosage? I'm worried about miscarriage or any complications for the baby. Please help ( i got miscarried last year but not sure of the reason)
Thank you for writing to ATD.
Thyroid hormones, specifically thyroxine, are essential for normal fetal brain development. Sub-clinical hypothyroidism is diagnosed in asymptomatic women when the thyroid-stimulating hormone level is elevated and the free thyroxine level is within the reference range.
The thyroid function test results of healthy pregnant women differ from those of healthy non-pregnant women. This means that the interpretation of the thyroid function tests needs to be pregnancy-specific and ideally trimester-specific reference intervals.
SCH has been associated with adverse maternal and fetal outcomes especially in women who are positive for antithyroid antibodies. However, most guidelines also say that due to the lack of randomized controlled trials there is insufficient evidence to recommend for or against universal thyroxine treatment in pregnant women with SCH. If your doctor has started you on thyroxine therapy with good reason, I suggest that you continue the said dose for 6 weeks and then repeat your TSH levels to check if you are hypothyroid or not.
Hope this helps.
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