Thyroid disease in pregnancy

Thyroid diseases are common in women of childbearing age and it is well known that untreated thyroid disturbances result in an increased rate of adverse events, particularly miscarriage, preterm birth and gestational hypertension. Furthermore, thyroid autoimmunity per se seems to be associated with complications such as miscarriage and preterm delivery. While strong evidence clearly demonstrates that overt dysfunctions (hyper- or hypothyroidism) have deleterious effects on pregnancy, subclinical disease, namely subclinical hypothyroidism, has still to be conclusively defined as a risk factor for adverse outcomes. Additionally, other conditions, such as isolated hypothyroxinemia and thyroid autoimmunity in euthyroidism, are still clouded with uncertainty regarding the need for substitutive treatment.