Bronchopulmonary Sequestration with Fetal Hydrops in a Monochorionic Twin Successfully Treated with Multiple Courses of Betamethasone.

 We present a case of severe bronchopulmonary sequestration (BPS) and fetal hydrops in one of the monochorionic twin successfully treated with multiple courses of betamethasone.  A 21-year-old gravida 2 para 1 was referred to our hospital for suspected twin-to-twin transfusion syndrome (TTTS) at 28 weeks of gestational age. However, prenatal ultrasound of the larger twin revealed a chest lesion that was associated with significant ascites, massive hydrothorax, scant hepatomegaly, subcutaneous edema, and severe polyhydramnios.