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': 'During uterine contraction of labour, the uterine blood flow : \nSelect and explain. \nA. Decreases, B. Increases, C. Does not change, D. Temporarily cases', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Decreases', 'role': 'assistant'}]