Hypothyroidism and pregnancy

[ElizabethM]

Hi all. My doc increased my levo to 50mcg some months back and my TSH is now down to 0.8. However, I have noticed my goitre seems slightly bigger approx a month after I learned I was pregnant (currently 13 weeks into my pregnancy). Have any of you ladies experienced this? Thanks.

[Clutter]

ElizabethM,

Was your dose increased when pregnancy was confirmed and have your TSH and FT4 been tested since pregnancy was confirmed?

[ElizabethM in reply to Clutter]

Dose was increased shortly before pregnancy was confirmed. Only TSH been tested since learning I'm pregnant and value came back as 0.8.

[Clutter in reply to ElizabethM]

ElizabethM,

TSH 0.8 was good. As your goitre has increased which may indicate your thyroid is trying to produce more thyroid hormone it may be worth asking for TSH to be tested again. Ideally TSH will be between 0.4 - 3.0 during the second and third trimesters.

Management of primary hypothyroidism: statement by the British Thyroid Association Executive Committee

The serum TSH reference range in pregnancy is 0·4–2·5 mU/l in the first trimester and 0·4–3·0 mU/l in the second and third trimesters or should be based on the trimester-specific reference range for the population if available. These reference ranges should be achieved where possible with appropriate doses of L-T4 preconception and most importantly in the first trimester (1/++0). L-T4/L-T3 combination therapy is not recommended in pregnancy (1/+00).

onlinelibrary.wiley.com/doi...

[ElizabethM]

Thanks for that, Clutter. I'm having my levels re-tested in a couple of weeks. My concern was more along the lines of whether it's "normal" for a pre-existing goitre to enlarge during pregnancy, even if you're on medication. I've searched online but I can't seem to find a definitive answer. Everything points to "yes, goiters can get larger during pregnancy" but it's not clear whether this refers to goitres on medicated/unmedicated persons.