Women's health refers to the health of women, which differs from that of men in many unique ways. Women's health is an example of population health Women also need health care more and access the health care system more than do men. While part of this is due to their reproductive and sexual health needs, they also have more chronic non-reproductive health issues such as cardiovascular disease, cancer, mental illness, diabetes and osteoporosis. Women's health indicators are measures that can be used to reflect the state of health of women in a given area. Some women's health indicators (e.g., breast cancer incidence) have been increasing in some developed and developing countries since the 1970s, coinciding with widespread changes in the global environment. Such geographic and temporal trends can present research and prevention opportunities. Changes in women's health indicators by time, place, and person provide clues that can be exploited by epidemiologists.