In 107 infants with 182 antenatally diagnosed urinary tract anomalies, 24 had either unilateral (12) or bilateral (12) vesicoureteric reflux (VUR). The VUR was more common in boys (male to female ratio, 16:8) and usually severe (grades IV [16], III [10], II [4], and I [6]). Intravenous pyelography showed the changes of atrophic pyelonephritis in 10 refluxing units, and in another two with an associated pelviureteric junctional hydronephrosis. Lateral ectopia of the ureteric orifices was noted in six of these 10 refluxing renal units. Isotopic renography showed a reduction in function in nine of the 14 patients examined, ranging between 9% and 41%. (45% and above was considered within the normal range). Only two patients developed a urinary infection before intravenous pyelography or isotopic renography was performed, suggesting that renal changes noted were primary rather than secondary. Findings support the hypothesis that foetal VUR may be a contributing factor in the causation of atrophic pyelonephritis (foetal reflux nephropathy) observed in these patients.