Ample progesterone must be produced by the ovarian corpus luteum to maintain early pregnancy. In fact, low progesterone secretion in the luteal phase has been implicated in habitual abortion. It was, therefore, logical to hypothesize that antiprogestins given during early pregnancy might act as abortifacients, and thus provide a medical alternative to current techniques of surgical abortion. Almost a decade of research is now available on the use of one of the antiprogestins, mifepristone, for first-trimester abortion. Drug regulatory officials in France, Sweden, and the United Kingdom have concluded that mifepristone, when given in combination with prostaglandin, is safe and efficacious medical treatment for early pregnancy termination.
Recommendation No. 8. The committee recommends expeditious submission to the U.S. Food and Drug Administration of all existing preclinical and clinical trial data on mifepristone and prostaglandin for early pregnancy termination to determine whether these data meet current U.S. regulatory requirements.
Recommendation No. 9. The committee recommends that in considering the use of mifepristone and prostaglandin for early pregnancy termination in women who smoke more than 10 cigarettes per day or are over 35 (two groups of women who were excluded from European studies), the documented risks must be compared with the risks of continuing pregnancy or of surgical termination of pregnancy. Furthermore, such assessment should attempt to distinguish between the risks attributable to mifepristone and those attributable to prostaglandin.
Recommendation No. 10. With respect to using mifepristone for first-trimester termination of pregnancy, health services research should be conducted in the United States to determine which approaches (e.g., required number of visits, type of health care provider administering the drugs, site of service delivery) are most suitable from the standpoint of safety, efficacy, accessibility, and acceptability.
The committee does not recommend that consideration of a New Drug Application by the Food and Drug Administration for the use of mifepristone for pregnancy termination be delayed until the research outlined in Recommendations Nos. 9 and 10 has been completed.