There is significant disagreement about the definition of menopause.
Some confusion exists because there are several stages of the natural menopause process.
Technically, natural menopause is the transition between perimenopause and postmenopause, the entire process culminating with the ceasing of the menses, generally around age 50 for most women. This natural menopause process itself is usually identified retrospectively, when it's been a year since a last period. It can be viewed as a hormonal shift mirroring puberty. Natural menopause occurs when the monthly cycle of ovulation comes to an end. This is because the ovarian supply of follicles and eggs declines sharply as a woman approaches menopause.