What Are Progestin-Only Injectables?

• The injectable contraceptives depot medroxyprogesterone acetate (DMPA) and norethisterone enanthate (NET-EN) each contain a progestin like the natural hormone progesterone in a woman’s body. (In contrast, combined injectable contraceptives contain both estrogen and progestin and must be given monthly, see Chapter 5 – Monthly Injectables.)
• They do not contain estrogen, and so can be used throughout breastfeeding, starting 6 weeks after giving birth, and by women who cannot use methods containing estrogen.
• After injection, the hormone is released slowly into the bloodstream. (See Chapter 5 – Monthly Injectables).
• They are usually injected into the muscle (intramuscular injection). A newer formulation of DMPA can be injected just under the skin (subcutaneous injection). (See DMPA for Subcutaneous Injection.)
• DMPA, the most widely used progestin-only injectable, is also known in its intramuscular form as “the shot”, “the jab”, the injection, Depo, Depo-Provera, and Petogen. The subcutaneous version (DMPA-SC) comes in two forms: the Uniject injection system currently marketed under the name Sayana Press; and the prefilled single-dose disposable hypodermic syringes marketed as Depo-SubQ Provera 104. The Uniject system allows DMPA-SC to be easily self-injected by clients who wish to do so.
• NET-EN is also known as Noristerat, Norigest, and Syngestal. (See the job aid Comparing Injectables for differences between DMPA and NET-EN.)
• Progestin-only injectables work primarily by preventing the release of eggs from the ovaries (ovulation).