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revised Tuesday July 30 2013
healthy sexuality
Birth Control Methods

Contraceptive Injections (Depo-Provera)

Depo-Provera is a hormone (progestin) given by injection (a needle) every 12 weeks to prevent pregnancy.

Depo-Provera prevents pregnancy by stopping the ovary from releasing an egg each month. Depo-Provera also makes the mucus in your cervix thicker, which makes it difficult for sperm to reach an egg.

Using Depo-Provera

Depo-Provera is recommended for women who:

  • Can't take the Pill or the Patch because of side effects.
  • Often forget to take their birth control pill.
  • Are 35 and over and smoke.
  • Want a birth control method that is private and effective.

Starting Depo-Provera

A physician must prescribe this medication. He or she will ask you about your health history and will do a breast exam and Pap test. You’ll also be given information and have the opportunity to ask questions before deciding to have the injection.

Once injected, this medication will remain in your body for many months, so it’s important that you understand all the information before receiving first injection.

If you decide to have the injection, you’ll get your first needle:

  • Between days 1-5 of a normal period OR
  • Within the first five days after an abortion or miscarriage OR
  • Six weeks after having a baby.


Depo-Provera is 97% effective in preventing pregnancy if you get your injection every 12 weeks. In other words, only three in 100 women who use it for one year will get pregnant.*  If you wait longer than 13 weeks between injections you risk an unwanted pregnancy.

* source: The Mayo Clinic


Advantages & Disadvantages



  • It’s convenient: only one injection four times a year.
  • It’s effective immediately if you get the injection within the first 5 days of your period.
  • It can be used by women who smoke, are over 35 years of age or are breastfeeding.
  • It may reduce the risk of endometrial cancer.
  • Doesn't protect against sexually transmitted infections or HIV.
  • May cause irregular periods, extra bleeding, and/or missed periods.
  • May cause weight gain, mood changes and headaches.
  • Once it's in your body, you can't stop any side effects that you might experience. You'll have to wait until the 12 weeks for the hormone to clear your system.
  • May cause reduced bone density
  • Might affect bone density in youth which may lead to osteoporosis later in life.
  • It may take up to two years after your last injection to become pregnant.

Cautions & Things to Consider

Depo-Provera Isn’t for Everyone.

Depo-Provera Doesn’t Protect Against STIs

Depo-Provera won’t protect you or your partner from STIs including HIV/AIDS or Hepatitis B.  Using Depo-Provera and condoms at the same time can reduce your chances of getting an STI, including HIV/AIDS.

You shouldn’t use a contraceptive injection if:

  • You’re pregnant.
  • You want to get pregnant within 1-2 years.
  • You have a family history of breast cancer, stroke, blood clots, liver disease or depression.
  • You have abnormal vaginal bleeding, liver problems, breast cancer or other breast problems.
  • You can’t commit to returning for an injection every 12 weeks. If you wait longer than 13 weeks between injections you risk an unwanted pregnancy.

If you have diabetes, breast cancer or problems with blood cholesterol you may be able to use Depo-Provera; however; you’ll need to be assessed and monitored more closely. Some women with these concerns might not be able to use Depo-Provera.


Possible Side Effects


There may be some effect on bone growth in young teen women who are still growing and using Depo-Provera. This may cause osteoporosis later in life. There are other factors associated with osteoporosis including diet, exercise, and family history. Talk to your family doctor about any family history of osteoporosis before using Depo-Provera.

Changes to Menstruation

Most females (9 out of 10) who use Depo-Provera have a change in their menstrual bleeding patterns. During the first six months of use, some females spot on and off, some bleed more frequently, and some don't bleed at all. Usually the amount of bleeding decreases with time but you may not know when to expect bleeding. After 12 months of Depo-Provera use, over 50% of women have no periods at all.

Delayed Planned Pregnancies

It may take up to two years after your last injection to become pregnant. On average, most females can become pregnant about nine months after stopping their Depo-Provera shots.

Weight Loss or Gain

A pattern of gaining or losing weight may continue as long as you continue with your injections. About 38-46% of women gain 1-3 kg (2-7 pounds) in the first year and about 24-40% of women lose weight..

Additional Side Effects

Additional side effects may include:

  • depression
  • headaches
  • breast tenderness
  • bloating
  • less interest in sex
  • nausea
  • acne

These side effects can continue for up to 8 months after your last injection.


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Revised: Tuesday July 30 2013

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