Morning-after pills can help prevent pregnancy if you've had unprotected sex — whether you didn't use birth control, you missed a birth control pill, you were sexually assaulted or your method of birth control failed.
Morning-after pills do not end a pregnancy that has implanted. Depending on where you are in your menstrual cycle, morning-after pills may act by one or more of the following actions: delaying or preventing ovulation, blocking fertilization, or keeping a fertilized egg from implanting in the uterus. However, recent evidence strongly suggests that levonorgestrel doesn't keep a fertilized egg from implanting. It's not clear if the same is true for ella.
Keep in mind that the morning-after pill isn't the same as mifepristone (Mifeprex), also known as RU-486 or the abortion pill. This drug terminates an established pregnancy — one in which the fertilized egg has attached to the uterine wall and has already begun to develop.
April 14, 2015
- Zieman M. Emergency contraception. http://www.uptodate.com/home. Accessed March 4, 2015.
- FDA approves Plan B One-Step emergency contraceptive for use without a prescription for all women of child-bearing potential. U.S. Food and Drug Administration. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm358082.htm. Accessed March 4, 2015.
- Shohel M, et al. A systematic review of effectiveness and safety of different regimens of levonorgestrel oral tablets for emergency contraception. BioMed Central Women's Health. 2014;14:54.
- Ella (prescribing information). Parsippany, N.J.: Watson Pharma Inc.; 2012. http://pi.watson.com/data_stream.asp?product_group=1699&p=pi&language=E. Accessed March 4, 2015.
- Plan B One-Step (prescribing information). Pomona, N.Y.: Duramed Pharmaceuticals Inc.; 2009. http://www.planbonestep.com/pdf/PlanBOneStepFullProductInformation.pdf. Accessed March 4, 2015.
- Koyama A, et al. Emerging options for emergency contraception. Clinical Medical Insights: Reproductive Health. 2013;7;23.