The practice of induced abortion—the deliberate termination of a pregnancy—has been known since ancient times. Various methods have been used to perform or attempt abortion, including the administration of abortifacient herbs, the use of sharpened implements, the application of abdominal pressure, and other techniques. A naturally occurring abortion that ends a pregnancy sometimes is described as a "spontaneous" abortion or, with the more frequently used popular euphemism, "miscarriage", to distinguish a difference between an induced abortion and a naturally occurring one, but medically, abortion is the terminology applied to either natural or induced.
Abortion laws and their enforcement have fluctuated through various eras. In much of the Western world during the 20th century, abortion-rights movements were successful in having abortion bans repealed. While abortion remains legal in most of the West, this legality is regularly challenged by anti-abortion groups. The Soviet Union under Vladimir Lenin is recognized as the first modern country to legalize induced abortion on demand. China used induced abortion as a state ordered birth control method during an effort to reduce the population in the twentieth century.