Endometriosis foci infiltrate deeply (more than 5 millimeters) one or more parts of the urinary tract. Common sites of infiltration are the bladder and/or ureters. When the bladder is infiltrated, deep endometriosis usually causes pain, increased frequency of urination and/or blood in the urine. When the ureters are infiltrated, endometriosis can cause severe narrowing (even obstruction) of the ureters without any warning signs of symptoms, eventually affecting normal kidney function (hydronephrosis and silent kidney loss).
