Hi, I'm sort of in the same boat. I am 47 and it is only really in the past year that it has dawned on me what all the symptoms may well be. However thinking back, I think symptoms started about 3 years ago. I don't think there is a definite starting point, its just something that gradually creeps up on you and then you start to add it all up, do some research, and figure out that you are peri menopausal. I would reckon it begins when you notice symptoms that are classic peri menopause symptoms. Will be interested to hear what others say!