Prune belly synrome is a rare birth defect affecting about 1 in 30,000 births. About 96% of those affected are male. Prune belly syndrome is a congenital disorder of the urinary system, characterized by a triad of symptoms. The syndrome is named for the mass of wrinkled skin that is often (but not always) present on the abdomens of those with the disorder. Other names for the syndrome include Abdominal Muscle Deficiency Syndrome, Congenital Absence of the Abdominal Muscles, Eagle-Barrett Syndrome, Obrinsky Syndrome, Fröhlich Syndrome, or rarely, Triad Syndrome.