Many different events and discoveries increased health care costs in various parts of the world over the duration of the twentieth century. One of the most important causes of rising costs has been development of increasingly expensive medical technologies such as x-ray machines, dialysis machines, MRIs, CAT scans, and much of the technology which prolongs care at the end of life, which tends to be extremely expensive. Similarly, our increasing ability to keep premature babies and people born with a variety of birth defects alive results in very high per capita costs which would not have been incurred in eras in which babies in less than perfect health tended to die. New drugs also, while saving people who might have died before their invention, also add to health care costs, especially drugs for relatively rare conditions that cannot achieve economies of scale. The ability to keep people alive for long periods with various chronic conditions also increases healthcare costs.
It should be noted that from a humanitarian perspective, the ability to keep people alive should not be considered simply as a cost, but also as a social and moral positive outcome.