Background: Non-immune fetal hydrops is a heterogeneous disorder with a mortality rate of 50-98%. Resolution of non-immune fetal hydrops is rare but has been reported to occur spontaneously or after targeted therapeutic measures.
Case: A euthyroid gravida with Graves disease presented with a history of three prior perinatal deaths between 26 and 28 weeks' gestation, all associated with fetal hydrops. In the current pregnancy, the fetus developed hydrops at 24 weeks' gestation. Fetal hyperthyroidism, with high-output cardiac failure, was diagnosed with fetal blood sampling. After maternal therapy with propylthiouracil, resolution of the non-immune hydrops were documented and a healthy neonate subsequently delivered to term. The neonate developed transient hyperthyroidism after delivery, which required treatment for 10 weeks.
Conclusion: Non-immune hydrops occurring as a result of fetal hyperthyroidism with high output cardiac failure is treatable with propylthiouracil.