Definition
By Mayo Clinic staffImplanon is a birth control (contraceptive) implant for women. Implanon is a flexible plastic rod about the size of a matchstick that is placed under the skin of the upper arm. It releases a low, steady dose of a progestational hormone to thicken cervical mucus and thin the lining of the uterus (endometrium). Implanon typically suppresses ovulation as well.
A newer version of Implanon also is available. It's called Nexplanon and it's radio opaque. This means it can be seen on X-ray, which is useful for checking the location of the implant. Implanon and Nexplanon are the only contraceptive implants with Food and Drug Administration (FDA) approval available in the U.S.
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- Implanon (prescribing information). Kenilworth, N.J.: Merck & Co., Inc.; 2009. http://www.implanon-usa.com/en/HCP/learn-about-it/full-prescribing-information/index.asp. Accessed Nov. 21, 2011.
- Birth control methods fact sheet. U.S. Department of Health and Human Services. http://www.womenshealth.gov/publications/our-publications/fact-sheet/birth-control-methods.cfm. Accessed Nov. 21, 2011.
- Nexplanon (prescribing information). Kenilworth, N.J.: Merck & Co., Inc.; 2011. http://www.merck.com/product/prescription-products/home.html. Accessed Nov. 21, 2011.
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- Etonogestrel implant. U.S. Food and Drug Administration. http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm?fuseaction=Search.DrugDetails. Accessed Nov. 18, 2011.
- Harms RW (expert opinion). Mayo Clinic, Rochester, Minn. Nov. 25, 2011.


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