This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Physiological Changes of Pregnancy, Subject name: Gynaecology & Obstetrics
[{'content': 'Least likely physiological change in pregnancy \nSelect and explain. \nA. Increase in intravascular volume, B. Increase in cardiac output, C. Increase in stroke volume, D. Increase in peripheral vascular resistance', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Normal pregnancy is characterized by increased plasma volume (preload), increased Cardiac Output and decreased PVR. These changes result in a physiologic decrease in mean blood pressure during the second trimester.', 'role': 'assistant'}]