Differential diagnosis of postpartum hyperthyroidism.
Postpartum thyroiditis is the most common cause of postpartum hyperthyroidism, even in patients with previous Graves' disease. The key to diagnosis is measurement of the thyroidal 1231 uptake, which is low in the 'destructive hyperthyroidism' of postpartum thyroiditis and normal or raised in the 'stimulatory hyperthyroidism' of Graves' disease.
