We report here a case of gastroschisis associated with bladder evisceration and complicated by rapidly developing hydronephrosis diagnosed antenatally. The timing of delivery was determined by the hydronephrosis, associated bowel dilatation and polyhydramnios. The case highlights the need for continuing ultrasonographic surveillance of fetuses with gastroschisis to identify further associated complications which were hitherto absent but whose presence may influence the timing of delivery and neonatal care.