Menopause is usually around 30 years. Women start to have menstruation from puberty, i.e. around 17 years old, and it will last for about 30 years, and then it will be normal at around 47-48 years old. If a woman is in good health or has good ovarian function, she may be able to prolong the amenorrhea period to 53-54 years old, which is also normal. Amenorrhea can also occur at the age of 45 if the ovaries are not functioning well or if there is a combination of poor nutritional status and endocrine disorders. When amenorrhea occurs before the age of 40, it is called premature ovarian failure, mostly due to ovarian failure or ovariectomy and other diseases that affect women. Amenorrhea is a natural physiological process and when a woman is not able to amenorrhea after the age of 55, the endometrium is affected by hormonal changes every month and can also lead to endometrial malignancy.