Early severe fetal Graves disease in a mother after thyroid ablation and thyroidectomy

Fetal Graves disease rarely presents before 26 weeks of gestation. We report a case of severe fetal Graves disease at 18 weeks of gestation in a mother who had very elevated Graves disease antibodies despite being several years post-thyroid ablative therapy and thyroidectomy.

A 36-year-old woman, gravida 1 para 0, with severe Graves disease post-radioiodine ablation followed by thyroidectomy on levothyroxine presented at 18 weeks of gestation for ultrasound examination. Her fetus was found to be severely tachycardic with a goiter. Propylthiouracil was initiated for fetal therapy. Delivery at 34 weeks of gestation was undertaken as a result of preterm premature rupture of membranes. The neonate experienced heart failure and pulmonary hypertension at birth but recovered with appropriate medical therapy.

It is possible for fetal Graves disease to develop as early as 18 weeks of gestation, and women who have had thyroid ablation and postsurgical hypothyroidism remain at risk for this serious pregnancy complication.