Nexplanon is a small, flexible, and rod-shaped contraceptive implant that is designed to be inserted under the skin of the upper arm by a healthcare professional. It releases a hormone called etonogestrel into the body over a period of up to three years, providing long-term protection against pregnancy. Nexplanon works by preventing ovulation, thickening cervical mucus to block sperm, and altering the lining of the uterus to prevent implantation of a fertilized egg. It is over 99% effective, making it one of the most reliable forms of birth control available. The implant can be removed at any time by a healthcare professional if pregnancy is desired or if the user wishes to stop using it.