Depo Provera

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What is Depo-Provera?

Depo-Provera is a hormone (progestin) given by injection every three months to prevent pregnancy.

How does it work?

In a normal cycle, hormones cause the ovaries to release an egg about once a month. Depo-Provera is an artificial form of one of these hormones. The hormone stops the ovary from releasing an egg each month. The hormone also causes the mucus in your cervix to thicken, making it difficult for sperm to enter the uterus. It also causes the lining of the uterus to thin, making it difficult for a fertilized egg to attach.

How effective is Depo-Provera?

Depo-Provera is 99.7 per cent effective in preventing pregnancy. It does not protect against sexually transmitted infections (STIs). You need to use condoms every time you have sex to help protect you from STIs.

How do I use Depo-Provera?

Your health care provider must prescribe this medication. You will be asked about your health history and have a breast and pap exam if it has not been done in the past year. You will be given information and have the chance to ask questions before you decide to have the injection. Because this medication stays in your body for many months, you must understand all the information before starting.

The first needle is usually given within the first five days of the start of your period and is effective right away. After that, you need to get the injection every 10 to 12 weeks.

What happens if I forget to come in for my injection?

If it has been 13 weeks since your last injection, you will need to have a pregnancy test done before your next injection. And you will need to not have sex or use backup birth control, like condoms, for four weeks after the injection.

If you have unprotected sex during a time that Depo-Provera is not effective, contact the Sexual Health Clinic, your health care provider or a pharmacist about the need for the emergency contraceptive pill (ECP).

What are the advantages to using Depo-Provera?

• very effective, reversible method of birth control
• lighter periods or no periods after being on Depo-Provera for a year
• convenient and private—only four injections a year, no one will know you are using it
• low cost—less than the pill, patch or ring
• reduced risk of cancer of ovaries or lining of the uterus
• less risk of pelvic inflammatory disease (PID)
• very few drug interactions. However you should always check with your health care provider or a pharmacist before taking any other medications.

What are the side effects or possible complications?

• Depo Provera increases the risk of osteoporosis (weakening of the bones). If you have other risk factors (slim build, lack of exercise, smoking, poor calcium intake or family history of osteoporosis), it may not be the right choice for you. You can discuss your situation with your health care provider. A bone density test may be required.
• During the first three to six months you may have irregular bleeding or spotting. This bleeding usually decreases over time. After a year on Depo-Provera, 55 per cent women report having no monthly period at all.
• Some women gain weight on Depo-Provera. This can be due to an increased appetite. Some women don’t gain weight and some women even lose weight. You can help to control your weight by eating a healthy diet and being physically active.
• You may experience other side effects such as; headaches, breast tenderness, nausea, acne, changes in mood, or decreased sex drive.
• Depo-Provera may affect a fetus if used during pregnancy.
• It may be harder to get pregnant for up to two years after you stop Depo-Provera. However most women are able to become pregnant within one year.
• Women who have a history of depression may find that Depo-Provera can worsen their condition. Discuss your situation with your health care provider.

Serious side effects are rare, but if you notice any of the following, get medical attention immediately:

• sudden and severe pain in the head, chest, abdomen or legs
• blurring or loss of vision, speech problems
• unusually heavy bleeding
• increased thirst or frequent need to empty your bladder
• infection at the injection site.

What else do I need to know?

It is important to have a yearly physical, while you are on Depo-Provera.