The letter, which was released on August 23, just a month prior to the FDA's approval of the abortion pill, cautioned doctors that the drug was approved only for use against gastric ulcers. The letter continued to note other potential side effects, including uterine rupture and possible unknown effects on the future well-being of both mother and child. To induce early abortion, the treatment involves three visits to a doctor or clinic. Following a physical exam, pregnancy test and ultrasound exam to date the pregnancy, a woman is given three mifepristone tablets to take in the office. Within two days, the woman returns to the doctor's office and takes two tablets of misoprostol.
Mifepristone blocks the hormone progesterone that's needed for a pregnancy to continue.
Misoprostol causes the uterus to contract and expel the fetus. Six hours following the dose of misoprostol, most women will complete the abortion. Bleeding or spotting can last an average of nine to 16 days. The woman returns to the doctor a third time about 12 days after getting the drugs to be sure the pregnancy has ended. Studies published in the New England Journal of Medicine and Archives of Family Medicine in 1998 show the pill is 92 percent effective in terminating pregnancies up to 49 days in duration, or within the first seven weeks of pregnancy.