“Menopause” is really a point in time – the last menstrual period – though the term gets used to describe the whole process.
Typically, in Britain, the average age for the last period is 50 years old, but this can vary quite a lot from individual to individual.
It is generally stated that a normal range of ages would be between 45 and 55 years.
Earlier than 45 is considered a “Premature Menopause”. This can come about naturally, or can be precipitated by medical treatment such as surgery in or around the ovaries, chemotherapy or radiotherapy.

I wondered whether you could include additional information about the length of time the change of life might last. I have been having very difficult symptoms – sweats, sleep problems, hot flushes – for 16 years and wonder if it can go on much longer. I have tried HRT and some alternative therapies/medications although would prefer not to take anything. Has anyone come up with any other cases that have lasted this long. The only other person I have ever heard of is Claire Raynor.