23
Recommendations Table 10. Subclinical Hypothyroidism
Preconception and in Pregnancy
Strength
*
Level
#
Profound maternal subclinical hypothyroidism (i.e., a
TSH >10 mU/L) during pregnancy should be treated with
levothyroxine.
Good Practice Statement
For mild maternal subclinical hypothyroidism diagnosed in
the first trimester,
a
levothyroxine treatment may be considered.
Conditional Low
For mild maternal subclinical hypothyroidism diagnosed
aer the first trimester,
a
levothyroxine treatment should not
be offered and follow-up TSH testing can be performed aer
4–6 weeks.
Strong High
For maternal subclinical hypothyroidism treated with
levothyroxine, TSH may be checked every 4 weeks until
midgestation and at least once around 30 weeks gestation.
Conditional Low
For women using levothyroxine prior to or during pregnancy,
a TSH within the normal range but below 2.5 mU/L may be
targeted.
Conditional Low
a
Trimester cut-offs are pragmatically defined and do not reflect thyroid-related physiolog y. erefore,
it is reasonable to adjust this cut-off by several weeks on a case-by-case basis.
* Strength of Recommendation;
#
Level of Evidence; Good Practice Statement.
Recommendations Table 11. Thyroid Autoimmunity
Preconception and in Pregnancy
Strength
*
Level
#
For euthyroid TPOAb and/or TgAb positive pregnant
women, levothyroxine treatment should not be offered.
Strong High
For euthyroid TPOAb and/or TgAb positive pregnant
women, do not offer selenium supplementation.
Conditional Moderate
For euthyroid TPOAb and/or TgAb positive pregnant
women, do not offer glucocorticoids or intravenous
immunoglobulin treatment.
Conditional Low
See Recommendations Table 1 for guidance on follow-up thyroid function testing.
* Strength of Recommendation;
#
Level of Evidence; Good Practice Statement.