A ureterocele is swelling in one of the tubes (ureters) that carry urine from the kidney to the bladder. The swelling can block urine flow.
A ureterocele is a birth defect.
Causes, incidence, and risk factors
A ureterocele occurs in the lower part of the ureter, where the tube enters the bladder. The swelling prevents urine from moving freely into the bladder. The urine collects in the ureter and stretches its walls, blowing it up like a water balloon.
Ureteroceles occur in about 1 in 500 to 1 in 4,000 people. Caucasians are most likely to be affected. Ureteroceles are equally common in left- and right-side ureters.
