This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Blood in urine in a patient in labour, with history of previous LSCS. The diagnosis is: 
Select and explain. 
A. Impending scar rupture, B. Urethral injury, C. Obstructed labour, D. Cystitis
C: Obstructed labour
Answer: C: Obstructed labour 
Explanation: In obstructed labour, the bladder becomes an abdominal organ and due to compression of urethra between the presenting pa and symphysis pubis, the patient fails to empty the bladder. The bladder walls gets traumatised which may lead to blood stained urine, a common finding in obstructed labour. The base of the bladder and urethra which are nipped in between the presenting pa and symphysis pubis may undergo pressure necrosis. Ref: Textbook of Obstetrics by DC Dutta, 6th edition, Page 405.