This is often followed by profuse sweating and then cold shivering as body temperature readjusts. They are more common in the evening and during hot weather. They can hit as often as every 90 minutes. Each one can last from 15 seconds to 30 minutes - 5 minutes is average. Seventy-five to eighty percent of women going through menopause experience hot flashes.
Hot flashes bother some women more than others.
Sometimes heart palpitations accompany hot flashes. Hot flashes occur sporadically and often start several years before other signs of menopause. They gradually decline in frequency and intensity with age. Eighty percent of all women with hot flashes have them for 2 years or less, while a small percentage have them for more than 5 years. Hot flashes can happen at any time.