This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abnormal labor, Subject name: Gynaecology & Obstetrics
[{'content': 'In primi, preterm labour, all of the following can be used as Tocolytic except: \nSelect and explain. \nA. Ritodnne, B. MgSO4, C. Dexamethasone, D. Propranolol', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ritodrine is a beta sympathomimetic drug. It was previously used as iv infusion. Now not used because of severe adverse effects like tachycardia and pulmonary edema TEXTBOOK OF OBSTETRICS, SHEILA BALAKRISHNAN, 2nd EDITION pg:195', 'role': 'assistant'}]