Not to be confused with a fever, hot flashes can appear suddenly with a stiflingly stuffy hot feeling and reddened sweaty head, face, and neck skin lasting from a few seconds to several minutes. Chills often follow them. Hot flashes occur in over 75% of women at menopause and may occur for more than 5 years. Pregnant women may also experience hot flashes. Menopausal-aged women frequently experience these sudden hot spells with profuse perspiration during the day or night.