The clinical signs are usually mild, and the thyroid is usually normal size. In contrast to the patient with HG, most women in whom the diagnosis of hyperthyroidism due to Graves' disease is made have had hypermetabolic symptoms prior to pregnancy. The goiter is nontender, diffusely enlarged, firm, homogeneous, frequently with a bruit. Ophthalmopathy includes lid retraction, widened palpebral fissures, lid lag on downward gaze, infrequent blinking. Occasionally pretibial myxedema, and acropathy is also present.
Elevated thyroid stimulating immunoglobulin confirms the diagnosis.
Pathophysiology Graves' disease is an autoimmune disease mediated by antibodies to the TSH receptor which usually act to stimulate the thyroid follicular cells. The disease may flare transiently in first trimester, but thereafter is usually suppressed during pregnancy. The thyroid is enlarged. Evaluation should be limited to rule out cancer. Antithyroid drugs should be used in these conditions until definitive therapy can be undertaken.