Transient hydrops fetalis of the donor fetus in twin-twin transfusion syndrome after therapeutic amnioreduction.

We present a case of twin-twin transfusion syndrome associated with transient hydrops fetalis observed in the donor after therapeutic amnioreduction at 22 weeks of gestation. After the amnioreduction, the bladder of the donor could be visualized and the donor subsequently began to make amniotic fluid, with spontaneous regression of hydrops fetalis. It is suspected that after therapeutic amnioreduction, intrauterine hemodynamic changes occurred and the donor developed transient hydrops fetalis due to volume overload.