The Depo-Provera Injection

How does the Depo shot work?

The Depo shot is an injection of a hormone – a progestin – that prevents pregnancy by stopping ovulation (the release of an egg). The shot needs to be repeated every 3 months, which means you need to get another injection every 11-13 weeks.

The Depo shot is 94 percent effective in actual use (6/100 users get pregnant per year) and can be even more effective if you always get your shots on time. This makes Depo one of the most effective forms of birth control available (more effective than the birth control pill, patch and ring, but less effective than IUDs).

How do I start the Depo shot?

If you are starting it after an abortion:

  • You can get the Depo shot the day of or the day after an aspiration abortion and it will protect you right away.
  • It is recommended to get the shot the day after you take the misoprostol pills with a medication abortion. If you do, it will protect you right away.

If you are starting it at another time:

  • The Depo shot is effective immediately if you get it during the first 5 days of your period.
  • If it is not the first 5 days of your period, it takes 7 days to start working. You can back up with condoms or not have sex until the 8th day after your very first shot. This is only for the first shot. After that, as long as you get the next shot on time, you will be continually protected against pregnancy.

 Where can I get the Depo shot?

You need a prescription from a doctor in order to get the Depo shot. You can get one from your family doctor or from a youth, sexual health, walk-in or women’s clinic. These places will usually be able to do the injection for you.

How much does it cost?

The Depo shot typically costs $40-$50 per injection. It may be covered under extended health plans including First Nations Status, Social Assistance and Disability, and private health insurance plans. Talk to your pharmacy for more information.

 What should I do if I am late for an injection?

If there are more than 13 weeks in between injections, you are considered late for your shot. Back up with condoms or don’t have sex until you have restarted your Depo (see the section above on how to start the Depo shot for more information). If you have unprotected sex more than 13 weeks after your last shot, you can use Emergency Contraception methods such as Plan B (50 percent effective), Ella (60 percent effective) or the Copper IUD (99.9 percent effective) to reduce the chance of pregnancy. See our website at www.ewhc.ca for more information.

 How will Depo affect my periods?

The most common side effect of Depo is irregular bleeding and changes to periods. This is common in the first few months of use and it tends to get better over time. Your period may become irregular or stop altogether over time. There is up to a 50 percent chance of periods stopping after one year of using Depo. This is because the Depo thins the lining of the uterus each month and is normal – not something to worry about. Depo can also help with ovulation pain, menstrual cramps and other period symptoms such as mood changes, headaches, breast tenderness and nausea.

 What kind of side effects can the Depo shot have?
Depo is associated more strongly with weight gain than other birth control methods, with up to 40 percent of users stopping Depo due to weight gain. However, not all studies show evidence of weight gain with Depo and some users may also lose weight or stay the same weight. Teenagers are at higher risk of weight gain than other users. Other side effects reported with the Depo shot include headaches, mood changes, acne, decreased libido (sex drive), nausea, breast tenderness, abdominal pain or discomfort, nervousness, dizziness, and fatigue. The most common of these side effects is headaches. Studies do not show that Depo causes an increase in depression, but if you experience severe depression, it may be good to talk to your health care provider about whether the Depo shot is suitable for you.
Perhaps the biggest disadvantage of Depo is that it is not rapidly reversible. This means that if you decide to stop using it due to side effects, the side effects can last 6-8 months after the last injection even though the birth control effect only lasts three months.

 What kinds of benefits does the Depo shot have?

Depo has the advantage of being a very effective and convenient method that is easy to use. You do not have to do something every day, week or month for it to work. There is nothing for anyone to find (such as pill packaging) so it is easy to keep private. It only contains progestin, so it is safe for to use for those who cannot use estrogen. For some people the possibility of having fewer, lighter or no periods is a strong benefit, as is the help with other menstrual symptoms like cramping, headaches and so on. Depo may also lower the risk of anemia, fibroids and bleeding from fibroids, pelvic infection, ectopic pregnancy, endometrial and ovarian cancer, pain from endometriosis, sickle cell crisis, and the frequency of seizures.

Who should not use the Depo shot?
You probably shouldn’t use Depo if you have a current diagnosis of breast cancer or have a recent history of breast cancer, serious liver problems or unexplained vaginal bleeding.

How quickly can I get pregnant after stopping the shot? Depo has no permanent effects on fertility, but it can take quite a while to wear off. It is possible to get pregnant 3 months after your last shot. If you do not want to get pregnant, you should start another method of birth control no later than 3 months after your last shot. However, sometimes it can take time for fertility to return –up to a year or more. The longer you are on Depo the longer it may take to get pregnant. If you want to get pregnant in the near future, Depo may not be the best choice for you. You may want to use a birth control method where fertility returns very quickly after you stop using them (such as an IUD, or the birth control pill, patch or ring).

Does Depo affect my bones? The use of Depo is associated with decreased bone density. However, this decrease is most rapid in the first 2 years of use and research has shown that it is largely reversible once you stop using Depo. It also does not appear to increase the risk of osteoporosis or fracture (breaking bones). Your health care provider may recommend taking supplements such as calcium and Vitamin D while you take Depo and/or getting regular exercise to keep your bones strong.

 Do I need to stop using Depo after 2 years? No, it is no longer considered necessary to stop using Depo after 2 years and it can be safely used for longer.

Does it cause cancer? There is no evidence that Depo use increases your risk of cancer, including breast and cervical cancer. And Depo actually prevents some kinds of cancer, such as endometrial and ovarian cancer!

Does the Depo shot protect me against sexually transmitted infections (STIs)?  No. Using condoms with the shot will provide you with protection against STIs as well as increasing your protection against pregnancy. It is also recommended to get tested regularly for STIs, which you can have done at our clinic.

Questions? Contact the Sex Sense Line at 604-731-7308 (1-800-739-7367) or www.sexsense.org

To contact our clinic call 604-322-6692 from 9:30 am to 4:00 pm from Monday to Friday.