mifepristone were given twice daily for three to six days accompanied by 0.25 mg sulprostone, an injectable prostaglandin (PGE2) analogue (Schering AG, Berlin), on the last day. With this combined regime, the overall frequency of complete abortion was 94 percent (Bygdeman and Swahn, 1985).
Subsequent studies (Bygdeman, Appendix B5) reported successful abortion rates of between 95 and 100 percent when mifepristone was combined with vaginal administration of 0.5 to 1 mg gemeprost, a vaginal pessary prostaglandin (PGE1) analogue. These high success rates for complete abortion led to the French approval in September 1988 of mifepristone used in conjunction with prostaglandin administration for pregnancies up to 49 days of amenorrhea as calculated from the last menstrual period.
In Great Britain, successful trials were conducted using gemeprost up to 63 days of amenorrhea. This protocol for medical interruption of pregnancy was approved in Great Britain in July 1991, and subsequently in Sweden in 1992, using the same vaginal prostaglandin protocol. The French have reported the largest experience, treating more than 2,000 women with up to 49 days of amenorrhea with a single 600-mg dose of mifepristone followed 36 to 48 hours later by the administration of either gemeprost (1 mg by vaginal suppository) or sulprostone (0.25 to 0.5 mg by intramuscular injection). In a study reported by Silvestre et al. (1990), the overall efficacy rate was 96 percent, with 1 percent continuing pregnancies, 2.1 percent incomplete expulsions, and 0.9 percent required dilation and curettage (D&C). Only one woman required blood transfusion.
The procedure is not only highly efficient, but it is generally acceptable to women. The clinical events of the mifepristone-gemeprost protocol are quite similar to those of a spontaneous abortion with bleeding and increased uterine contractility. About 50 percent of patients have begun to bleed at the time of prostaglandin treatment, and virtually all bleed within four hours after the administration of prostaglandin, with a mean duration of bleeding of eight days (Bygdeman, Appendix B5). Uterine pain is common, especially in the first few hours following prostaglandin treatment, with approximately 30 percent of women requiring an analgesic and another 30 percent requiring a narcotic.
In a large study in France, serious cardiovascular side effects following prostaglandin administration (sulprostone injection) were reported in 4 out of 16,000 women treated after sulprostone injection (Ulmann et al., 1992). These included one acute myocardial infarction and three cases of severe hypertension. By now, over 60,000 women have used RU 486 for abortions. Two more myocardial infarctions have occurred, one of which was fatal. The overall frequency of severe cardiac complications