Contraceptive Implant

Contraceptive implants contain progestin, which prevents pregnancy by stopping ovulation (that is, the release of eggs by the ovaries). These plastic capsules are inserted under the skin of the inner arm above the elbow and can remain in place for 5 years.

(From KS Saladin, Anatomy and Physiology, 1998, WCB McGraw-Hill, p. 1020; with permission. © The McGraw-Hill Companies, Inc./Bob Coyle, photographer)