This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Medical, surgical and gynaecological illness complicating pregnancy, Subject name: Gynaecology & Obstetrics
[{'content': 'The threshold of Middle cerebral aery peak systolic velocity for the diagnosis of fetal anemia is a value ------ for the gestational age \nSelect and explain. \nA. >= 1 MoM, B. >= 1.5 MoM, C. >= 3 MoM, D. >= 5 MoM', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The MCA PSV is an accurate noninvasive method for the diagnosis of fetal anemia. The threshold of for the diagnosis of fetal anemia is a value >= 1.5 MoM for the gestational age. Abnormally elevated MCA PSV has a sensitivity of 100% and false positive rate 12% for the diagnosis of fetal anemia. Reference: Practical guide to High Risk Pregnancy and Delivery; 3rd edition; Chapter 14; Rh Alloimmunization', 'role': 'assistant'}]