Injectable long-acting contraceptives.

Abstract

This paper reviews the pharmacologic and epidemiologic data on injectable contraceptives and provides clinicians with clinical insights pertaining to counseling selection initiation and maintenance to facilitate successful use of injectable contraceptives. In the US women have two available options: Depo-Provera (DMPA) a 3-month progestin-only formulation containing 150 mg medroxyprogesterone acetate per injection and Lunelle (MPA/E2C) a 1-month combination containing 25 mg medroxyprogesterone acetate and 5 mg estradiol cypionate per injection. Both DMPA and MPA/E2C offer users effective convenient and reversible birth control choices. In particular DMPA is characteristically associated with amenorrhea. This progestin-only control method can be used by lactating women and by others for whom contraceptive doses of estrogen are contraindicated. However return of fertility can be delayed in women discontinuing DMPA to become pregnant. In some cases use of DMPA also confers important noncontraceptive and therapeutic benefits. On the other hand MPA/E2C is more beneficial to women who are concerned with daily pill taking who prefer regular cycles to amenorrhea and who find monthly injections acceptable and accessible. Like oral contraceptives MPA/E2C also represents an appropriate choice for women who prefer a rapidly reversible contraceptive method. Its contraindications are parallel to those for combined oral contraceptives.