Depo-Provera (Injection Method)
What is Depo-Provera?
Depo-Provera is the hormone (progesterone) given by injection (a needle) every 12 weeks to prevent pregnancy.
How does it work?
The hormone stops the ovary from releasing an egg each month. It also makes the mucus in your cervix thicker. This stops the sperm from reaching the egg. Depo-Provera, if given every 12 weeks, is 99.7% effective in preventing pregnancy. The first injection is effective immediately if given in the first 5 days of a normal period.
Who may want to use Depo-Provera?
This method of birth control is only recommended if there are no other methods of birth control right for you. Women may consider, in discussion with their doctor, if they want to use this form of birth control if they:
- can't take the pill because of side effects
- have difficulty remembering to take birth control pills/using the patch
- are 35 and older and smoke
- want a birth control method that is private and effective.
Who should not use Depo-Provera?
Women should not use Depo-Provera if they:
- may be pregnant now
- may want to get pregnant within 1-2 years
- have a family history of breast cancer, stroke, blood clots, liver disease or depression
- will not be able to return for their injection every 12 weeks
- have any of the following medical problems: abnormal vaginal bleeding, breast cancer or other breast problems, liver problems, history of stoke, blood clots in your legs
- have not started their periods yet
The doctor will also ask about family history of cancer, high blood pressure, migraines, convulsions, diabetes, depression or any over-the-counter or prescription medications.
How do I start Depo-Provera?
Depo must be prescribed by a physician. Your health care provider will ask you about your health history including a breast, pelvic and Pap exam. You will be given information and have the opportunity to ask questions before deciding to have the injections. Because this medication stays in your body for many months, you must understand all the information before starting the injection.
If you decide to have the injection, the first needle is best given:
- day 1-5 of a normal period
- within the first 5 days after an abortion or miscarriage
- within the first 5 days after having a baby (if not breastfeeding) or six weeks after having a baby (if only breastfeeding.)
What is important to remember about Depo-Provera?
You need to get the injection every 12 weeks. If you wait longer than 13 weeks to get your next injection you can get pregnant. You will need to use another method of birth control such as condoms.
After stopping Depo, most women can get pregnant within an average of 10 months but it may take up to 2 years.
Risks of Using Depo-Provera
- Depo-Provera may decrease the amount of calcium in your bones which may increase your risk of osteoporosis and broken bones, particularly after menopause. Calcium is added to your bones in your teenage years. This decrease of calcium in your bones is especially important if you are a teen or have the following risk factors:
- bone disease
- anorexia nervosa
- strong family history of osteoporosis
- use medications for epilepsy or steroids
- drink alcohol or smoke cigarettes regularly
Depo-Provera should not be used for more than 2 years. If you must use Depo for more than 2 years, you should be tested for bone density. Health Canada has issued warnings regarding Depo-Provera and its effect on bone density. You may be advised to take calcium and vitamin D supplements.
- Irregular Menstrual Bleeding
The most common side effect of Depo-Provera is a change in the normal menstrual cycle. This can include: irregular or unpredictable bleeding or spotting, increase or decrease in menstrual bleeding, or no bleeding at all. Usually the amount of bleeding decreases with time but you may not know when to expect bleeding. After 12 months, over 50% of women have no periods and this is normal.
With continued use of Depo, many women stop having periods completely. When you stop using Depo-Provera your period will usually, in time, return to its normal cycle.
Are there any side effects?
A pattern of gaining weight may continue as long as you have your injections. About two thirds of women in studies report a weight gain of about 5 pounds (2 kilograms) during the first year and about 8 pounds (3.6 kilograms) over 2 years.
Some women may have other side effects such as: depression/nervousness, weakness or fatigue, vaginal discharge or irritation, headaches, breast tenderness, bloating, less interest in sex, nausea, acne, hot flashes, aches and pains.
If you have an increase in thirst or increased frequency in urination (peeing), or if you are feeling depressed, report that to the doctor at your next visit.
Serious side effects are rare but if you have any of the following warning signs, see a doctor right away:
- sharp chest pain, coughing of blood or sudden shortness of breath
- sudden severe headaches or vomiting, dizziness, fainting, problems with eyesight, speech, weakness or numbness in are or leg
- severe pain or swelling in the calf
- unusually heavy vaginal bleeding
- severe pain or tenderness in the lower abdominal area
- perisient pain, pus or bleeding at the injection site
Allergic reactions are rare. Symptoms include hives, itchiness, and/or difficulty breathing. This generally occurs within 15 minutes.
Depo-Provera does not protect you or your partner from sexually transmitted infections including HIV/AIDS or Hepatitis B. Use a condom every time you have sexual intercourse.
For more information, call 905-799-7700 and ask for Sexual Health Information.
Additional information available at: Health Canada: www.hc-sc.gc.ca