Background: Treatment with radioiodine for Graves’ disease regularly increases the level of antithyroid antibodies, and transplacental passage of stimulating thyrotropin receptor antibodies (TRAb) may cause fetal hyperthyroidism. Case presentation: A 21-year-old woman with Graves’ disease received radioiodine treatment to avoid use of antithyroid drugs in pregnancy. She became pregnant 4 months later and was euthyroid during pregnancy. In gestational week (GW) 33, she was admitted with an increased fetal heart rate of 176–180 beats/min. Fetal echocardiography indicated cardiac decompensation. The neonate had severe hyperthyroidism (free thyroxine >100 pmol/l, nv 12.0–22.0), cardiac insufficiency, insufficient weight gain, goiter and considerably accelerated skeletal age. In the mother and neonate, TRAb was >40 IU/l (nv <1.0), indicating transplacental passage of stimulating antibodies. After delivery, TRAb remained >40 IU/l in the woman, and 18 months later she underwent total thyroidectomy with subsequent decline in TRAb. In her next pregnancy, TRAb fluctuated between 38 and 17 IU/l, and repeated fetal ultrasound showed no goiter or sign of hyperthyroidism. In cord blood, TRAb was 10.9 IU/l, and the neonate had normal thyroid hormone levels. Conclusion: This case report illustrates the impact of maternal TRAb level for neonatal outcome in two successive pregnancies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.