RU486 contains the synthetic steroid mifepristone that interferes with the action of the body's progesterone (the hormone that builds up the uterine lining to prepare for pregnancy). A medical abortion typically consists of the use of two medications: RU486 (mifepristone), which causes a fertilized egg to not remain attached to the lining of the uterus, and misoprostol, which causes uterine contractions. The abortion pill is FDA-approved for women up to 7 weeks pregnant (5 weeks since conception) or up to 49 days after one's last menstrual period. RU486 helps to terminate a pregnancy (allowing a woman to completely pass the pregnancy) without surgery and is 92 to 98% effective when used in combination with misoprostol. When Mifepristone is used alone, it is only 64 to 85% effective. Although some healthcare providers will still use this method for women who are more than 7 weeks pregnant, use at this time is considered off-label (meaning, no longer FDA approved).
Advantages:
Disadvantages:
- Some people are morally opposed to this method, because conception has occurred prior to use.
- Mifepristone may not be an option for women with liver or kidney problems, anemia, diabetes, Rh-negative blood or those who are very overweight.
- This method requires several visits to the doctor and may not work if combined with other drugs, such as ibuprofen.
- Minor cramping
- Possible nausea
- Vomiting and diarrhea
- Bleeding can last 8 to 10 days
Source:
Spitz, I.M., Bardin, C.W., Benton, L. & Robbins, A. (1998). Early pregnancy termination with mifepristone and misoprostol in the United States. New England Journal of Medicine, 338(18), 1241-47. Accessed through private subscription 5/12/08.


