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
[{'content': "Increased acidosis and hypoxaemia is seen in: \nSelect and explain. \nA. Normal Doppler wave form, B. Increased fetal diastolic flow in the middle cerebral artery with absent diastolic flow in the aorta, C. Presence of the 'notch' in the uterine artery, D. Absent umbilical artery", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Doppler Study of Middle Cerebral Vessels:\n\nNormally the middle cerebral vessels have high resistance flow and are characterised by little diastolic flow.\nIn case of IUGR a brain-sparing effect is seen with a reduction in the resistance indices in the middle cerebral vessels (i.e. increased flow) due to the shunting of blood to the brain in IUGR. Whereas in other areas (as aorta in the options) show decreased flow.\n“Increased fetal diastolic flow in middle cerebral artery with absent diastolic flow in aorta implies fetal acidemia.”\n\nDutta Obs. 7/e, p 648\nAs far as persistence of diastolic notch in uterine artery is concerned, it signifies pregnancies destined to develop preeclampsia.', 'role': 'assistant'}]