This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Gynaecology & Obstetrics
Hot flushes are experienced as a result of 
Select and explain. 
A. Increased noradrenaline, B. Decreased estrogen, C. Increased noradrenaline and decreased estrogen, D. Increased noradrenaline and estrogen
C: Increased noradrenaline and decreased estrogen
Answer: C: Increased noradrenaline and decreased estrogen 
Explanation: Hot flushes are caused by noradrenaline, which disturbs the thermoregulatory system. Oestrogen deficiency reduces hypothalamic endorphins, which release more norepinephrine and serotonin. This leads to inappropriate heat loss mechanism. Other causes that can be associated with the symptom of hot flushes include: thyroid disease, epilepsy, pheochromocytoma, carcinoid syndromes, autoimmune disorders, mast cell disorders, insulinoma, pancreatic tumours and even leukemias. REF : Shaw book of gynecology