Screening for thyroid disease during pregnancy

Overt thyroid disease is a well-established risk factor for adverse pregnancy and perinatal outcomes. Whether or not subclinical thyroid dysfunction carries these same risks has been a matter of controversy. There is inconsistent evidence on the association of subclinical thyroid dysfunction (ie, subclinical hypothyroidism or isolated hypothyroxinemia) with a woman's pregnancy outcome or the cognitive development of her offspring and there are no interventional trials that have shown that women with subclinical hypothyroidism who are treated have improved outcomes. Until such data are available, it is premature to recommend universal screening for thyroid disease in pregnancy or treatment of women who have subclinical thyroid dysfunction.