Millions of women worldwide have safely terminated their pregnancies with medication since mifepristone—or RU 486—was first introduced in the late 1980s. Research in the past two decades has identified several highly effective regimens for early medical abortion. Whether taken in a health center or at home by women themselves, regimens using pills offer an option that many women prefer to surgical abortion procedures such as manual vacuum aspiration or dilation and curettage (D&C).

Misoprostol induces mucus and bicarbonate secretion as well edema of the mucosa and submucosa which causes thickening of the mucosal bilayer, which results in a reduced backflow of hydrogen ions and improved regulation of mucosal blood flow, which ultimately leads to the preservation of the mucosa's ability to produce new cells.