Choledochal cyst complicating a twin gestation.

Cystic dilatation of the common bile duct is rare and dangerous during pregnancy. We have described a case of a twin gestation and a concomitant choledochal cyst. Surgical release of the dilatation is urgent in light of the overdistended uterus. A conservative surgical approach in the antepartum period is supported by the successful outcome of this case.