question: i am 27 weeks pregnant, and had a history of UTI during my first trimester, and now, the problem i have is when after i urinate,a drop of blood comes next. I thought i was having some vaginal bleeding , but when my OB doctor checked on me, the blood was not from my cervix . I did KUB ultrasound and they found out that i am having a mild dilatation of pelvocalyceal system in my right kidney. but not demonstrable stone was seen. There is also a fullness of the right ureter . they found out also that there is urinary bladder sediments. and urinary retention of 21%. what does this means. thank you!