The menopause could last for around 12 years and is likely to affect women of certain races for longer than others, research suggests.
Women suffer from frequent hot flushes and other symptoms such as night sweats for an average of around seven years, a major US study has found.
It also revealed that for some, the symptoms lasted up to 11.8 years - far longer than originally thought.
Researchers discovered that the earlier women started experiencing menopausal symptoms - some while they were still menstruating - the longer they lasted.
For women who were post-menopausal when the hot flushes and other menopausal vasomotor symptoms (VMS) kicked in, they lasted on average for 3.4 years.
African-American women reported the longest total VMS duration.
Japanese and Chinese women had the shortest, with 4.8 years and 5.4 years respectively.
The median total VMS durations were 6.5 years for non-Hispanic white women and 8.9 years for Hispanics.
In the latest study, published in the journal JAMA Internal Medicine, researchers analysed 17 years of data from 1,449 women.
They each had frequent VMS, meaning they had suffered hot flushes or night sweats on at least six days in the previous fortnight.