Renal failure in the surviving monochorionic twin after death of the co-twin in utero.

Renal failure in the newborn infant is mainly determined by vascular causes. In this report we describe a patient with a particular vascular cause of renal failure. The patient was the product of a twin pregnancy in which the twin partner died in utero. In retrospect, the twins appeared to be monozygotic. As the pregnancy was studied carefully prenatally by ultrasound, we were able to observe the development of this condition, characterized by oliguria, oligohydramnios, and lung hypoplasia: the oligohydramnios sequence. After organ development had been normal initially, renal function was lost and the oligohydramnios sequence developed in the survivor after the co-twin had died in utero.