Women who desire to receive mifepristone to terminate a pregnancy must read a medication guide approved by FDA and sign an agreement form. The medication guide describes the treatment procedure, lists contraindications to mifepristone use, and describes possible adverse effects. Physicians must sign a separate agreement in order to receive supplies of the drug. They must confirm their ability to diagnose ectopic pregnancy and date pregnancies accurately. In addition, physicians must confirm that they can intervene surgically if the drug regimen causes severe bleeding or incomplete abortion or must agree to make the necessary referral arrangements in advance.
Mifepristone inhibits the activity of progesterone, which is required for continuation of pregnancy.
Mifepristone sensitizes the myometrium to the contraction-inducing effects of prostaglandins. The procedure requires three office visits. Two days later, she returns and takes a 400-mcg oral dose of misoprostol. A third visit is required about 14 days after the first visit to ensure that the pregnancy was terminated. There is a risk of birth defects if the drug regimen does not terminate the pregnancy.