[Prevention of thyroid disorders in pregnant women]

Iodine is essential for biosynthesis of thyroid hormones and daily iodine intake needs are increased during pregnancy. Thyroid dysfunctions (hypothyroidism, hyperthyroidism) are due to autoimmune diseases (Hashimoto's disease, Graves' disease) in most women of childbearing age. During pregnancy they are associated with maternal and fetal complications: maternal hypothyroxinemia during the first trimester of gestation can be associated with abnormal cognitive development and intellectual outcomes in the newborn and the children. In patients with Graves' disease, TSH-receptor antibodies cross the placenta and can induce fetal and neonatal dysfunctions.

In order to prevent maternal and fetal complications and ameliorate the pronostic of thyroid disorders in pregnant women, the prevention should be: a systematic prophylaxis of iodine deficiency in pregnant women; an adjustment of the preconception levothyroxine treatment in women with hypothyroidism diagnosed before the pregnancy; a targeted screening for maternal hypothyroidism in high-risk women; a rational measurement for TSH-receptor and anti-thyroperoxydase antibodies in some women with autoimmune thyroid diseases.