[Postpartum autoimmune thyroid syndrome].

Thyroid dysfunction frequently (around 5%) occurs after delivery through immune rebound mechanism. More than half of the patients suffer from postpartum thyroiditis. Initially, patients have a thyrotoxic phase, later passing through euthyroidism to hypothyroidism and, finally, return to euthyroidism. After delivery, other forms of autoimmune thyroid dysfunction also occur, including Graves' disease, transient hypothyroidism without preceding destructive thyrotoxicosis, and persistent hypothyroidism. To include all these conditions, the term postpartum autoimmune thyroid syndrome is often used. To predict who will develop postpartum thyroid dysfunction, the measurement of anti-thyroid microsomal antibody (MCAb) during pregnancy is useful because 62% of subjects with positive MCAb show thyroid dysfunction after delivery.