Ureteropelvic junction obstruction is a condition where blockage occurs at a point where the ureter attaches to the kidney. This leads to decrease of flow of urine down the ureter and thus increases the fluid pressure inside kidney. Higher pressure inside kidney leads to deterioration of kidney function. The obstruction can be either congenital (the patient is born with it) or can be develops because of age related or body shape issues. Your doctor will suggest the best treatment plan for your depending upon your health and medical history.