Chills are feelings of coldness accompanied by shivering. They may arise with or without fever. Without fever, chills typically arise after exposure to a cold environment. Essentially any condition that may produce fever (including infections and cancers) can result in chills along with fever. Fever and chills are common symptoms of influenza infection (the flu). Exposure to a cold environment can result in chills. With prolonged or constant exposure to cold, serious injuries related to hypothermia (a lowered core body temperature) can result. Chills in pregnancy are due to the same causes (hypothermia, infection) as chills in general.
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