An Injectable Contraceptive

Depo-Provera: An Injectable Contraceptive

What is Depo-Provera?

Depo-Provera (medroxyprogesterone acetate) is an injectable medicine (a “shot”) that prevents pregnancy for up to 3 months with each injection. Depo-Provera is a drug that is very similar to progesterone, a hormone normally produced by the ovaries every month as part of the menstrual cycle.

How does it work?

Depo-Provera prevents pregnancy by preventing ovulation (the release of an egg from the ovary). If your ovaries do not release an egg, you are unlikely to get pregnant. Depo-Provera is given as 1 shot in the buttock or upper arm. The first shot should be given within 5 days after the beginning of a normal menstrual period, and shots should be repeated every 3 months.

Is it effective?

Depo-Provera is as effective as tubal ligation (having your tubes tied) and more effective at preventing pregnancy than several other methods, including birth control pills, condoms and diaphragms. It does not, however, protect against HIV infection or any other sexually transmitted infections.

Is the effect permanent?

No. Depo-Provera only works for about 3 months. The shot must be repeated every 3 months to prevent pregnancy. After a woman stops using Depo-Provera, her normal ovarian function returns after a short time. However, it takes an average of 9 to 10 months to get pregnant after getting the last shot.

How long can I take it?

You should not use Depo-Provera for more than 2 years unless no other form of birth control is right for you. Using Depo-Provera can cause you to lose some of the calcium that is stored in your bones. The longer you use Depo-Provera, the more calcium you may lose. The calcium may not return completely once you stop using it. This can lead to osteoporosis.

Are there side effects?

Most women have some changes in their menstrual periods while using Depo-Provera, including irregular and unpredictable bleeding or spotting, an increase or decrease in menstrual bleeding, or no bleeding at all. After 1 year of use, about 50% of women have no bleeding at all. The absence of periods is not harmful, and periods usually return to normal after Depo-Provera is stopped. If unusually heavy or continuous bleeding occurs, you should see your doctor. Other possible side effects include weight gain, headaches, nervousness, abdominal discomfort, dizziness and weakness or fatigue.

Can I use it if I am breastfeeding?

Women who are breastfeeding can safely use Depo-Provera. Long-term studies of babies whose mothers used Depo-Provera while breastfeeding found no bad effects.

Who should not use Depo-Provera?

Women who have any of the following should not use Depo-Provera: liver disease, a history of blood clots (phlebitis) or stroke, vaginal bleeding without a known reason, cancer of the breast or reproductive organs, known or suspected pregnancy, or allergy to the drug in Depo-Provera.