RisksBy Mayo Clinic staff
Emergency contraception is an effective option for preventing pregnancy after unprotected sex, but it isn't as effective as other methods of contraception and isn't recommended for routine use. The morning-after pill also doesn't offer protection from sexually transmitted infections.
An estimated 1 to 2 women will become pregnant out of 100 women who have unprotected sex one time and correctly use the morning-after pill.
The morning-after pill isn't appropriate for everyone. Tell your health care provider if:
- You're allergic to any component of the morning-after pill
- You're taking certain medications that may decrease the effectiveness of the morning-after pill, such as barbiturates or St. John's wort
- You're breast-feeding (Plan B One-Step and Next Choice can be used during breast-feeding, but Ella isn't recommended)
In addition, make sure you're not pregnant before using Ella. The effects of Ella on a developing baby are unknown. However, if you're already pregnant when you take Plan B One-Step or Next Choice, the treatment will simply be ineffective and won't harm the developing baby.
Side effects of the morning-after pill typically last only a few days and may include:
- Nausea or vomiting
- Breast tenderness
- Bleeding between periods or heavier menstrual bleeding
- Lower abdominal pain or cramps
- 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 May 7, 2012.
- Plan B One-Step (prescribing information). Pomona, N.Y.: Duramed Pharmaceuticals Inc.; 2009. http://planbonestep.com/plan-b-prescribers/index.aspx. Accessed March 7, 2012.
- Next Choice (prescribing information). Corona, Calif.: Watson Laboratories Inc.; 2009. http://mynextchoice.com/pi.asp. Accessed March 7, 2012.
- Zieman M. Emergency contraception. http://www.uptodate.com/index. Accessed March 7, 2012.
- 5. Hatcher RA, et al. Contraceptive Technology. 20th ed. New York, N.Y.: Ardent Media; 2011:113.
- Emergency contraception. American Congress of Obstetricians and Gynecologists. http://www.acog.org/For_Patients. Accessed March 7, 2012.
- Spitz IM. Mifepristone for the medical termination of pregnancy. http://www.uptodate.com/index. Accessed March 7, 2012.
- Noe G, et al. Contraceptive efficacy of emergency contraception with levonorgestrel given before or after ovulation. Contraception. 2010;81:414.
- Noe G, et al. Contraceptive efficacy of emergency contraception with levonorgestrel given before or after ovulation. Contraception. 2011;84:486.
- Gemzell-Danielsson K. Mechanism of action of emergency contraception. Contraception. 2010;82:404.
- Prabakar I, et al. Emergency contraception. BMJ. 2012;344:e1492.
- 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 June 26, 2013.