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
Which of the following has highest relative risk for placental abruption 
Select and explain. 
A. Chorioamnionitis, B. Thrombophilia, C. Prior abruption, D. Preterm rupture of membrane
C: Prior abruption
Answer: C: Prior abruption 
Explanation: Relative Risk for placental abruption is seen with prior abruption > Thrombophilia > Chorioamnionitis > PROM.