Which of the following is considered a progestin-only birth control option?

Implanon is a progestin-only birth control option, which is a long-acting reversible contraceptive. It consists of a small rod that is implanted under the skin of a woman's upper arm and releases a synthetic form of the hormone progesterone. This continuous release of progestin effectively prevents ovulation, thickens cervical mucus, and alters the uterine lining, which helps to prevent pregnancy.

Progestin-only methods are particularly beneficial for individuals who cannot use estrogen due to health concerns or who experience side effects from combination hormonal methods. Implanon is highly effective, often lasting for up to three years, making it a convenient choice for those seeking long-term contraception without the daily responsibility of taking a pill or requiring frequent visits for injections.

Other options, like the cervical cap, function as barrier methods and do not involve hormonal mechanisms; Ortho Evra is a transdermal patch that releases both estrogen and progestin; and oral contraceptives typically contain both estrogen and progestin rather than being exclusively progestin-based. Therefore, Implanon stands out as a dedicated progestin-only option.