What is the normal age for perimenopause?

Most women enter perimenopause in their mid to late 40s. Given that the average age of natural menopause is approximately 51, the transition typically begins sometime in a woman's mid-40s and lasts anywhere from two to ten years. There is significant individual variation. The key thing to know is that hormonal changes can be well underway long before periods become irregular or stop, which is why symptoms in your late 30s or early 40s are worth taking seriously.