It's estimated that by 2025, around 1.1 billion of the women in the world will be diagnosed with menopause - a natural, hormonal condition that causes the menstrual cycle to cease.
Menopause typically happens in women between the ages of 45 and 55, when the ovaries stop releasing an egg every cycle. As a consequence, women can experience hormonal changes before menopause, during menopause, and even after menopause. Hot flashes - sudden waves of heat throughout the body - are common during menopause. Some women also report changes in mood, metabolism, sleep, and libido.
Although the condition is a natural part of aging, some women experience premature menopause due to exposure to cancer treatments, smoking, or removal of the ovaries. Loss of estrogen in menopause also makes women more likely to be at risk for osteoporosis and heart disease.
Watch the video to learn the theories behind why human females go through this process.