Fetal hydronephrosis: selection and surgical repair.

Newly developed diagnostic techniques allowed us to select a fetus with potentially reversible renal damage from the usually fatal group with bilateral hydronephrosis and severe oligohydramnios early in gestation. Fetal surgery to marsupialize the fetal bladder at 24 weeks gestation restored normal amniotic fluid dynamics and allowed sufficient pulmonary and renal development to insure survival after delivery near term.