This can also come about as a result of surgical removal of the ovaries as well as other surgical procedures. When menopause occurs naturally in women before the age of 45, it is called ovarian failure. Only a small percentage of women, however, fall into this category. The process of menopause usually lasts between one and two years with the onset occurring gradually, often five to eight years before. For most, menstrual periods begin to occur increasingly farther apart, as a result of the decreasing hormone levels.
Some women experience excessive bleeding or ususually short cycles.
A small percentage cease menstruation suddenly. Absence of menstruation is not a certain indication that menopause has occured, although this is the most common diagnosis if menstrual periods have been absent for at least one year. A conclusive medical test which measures the blood level of the follicle stimulating hormone made in the pituitary gland can give a more concrete diagnosis. However, this test can be affected by individual conditions within the woman's reproductive system. A hot flash is a sensation of heat that often spreads from the chest and waist area to the arms, face and neck.