The Depo Provera injection is a form of contraception. This page explains how the injection works and tells you how to get it.
What is Depo Provera?
Depo Provera is a contraceptive injection containing progestogen. It is commonly referred to as “the injection” or "DP".
Progestogen is similar to one of the hormones produced naturally in the ovaries. The injection is given every 12 weeks.
How does it work?
It prevents pregnancy by stopping the ovaries releasing an egg each month. There are also changes to the lining of the womb (endometrium).
How well does it work?
Typically, Depo Provera is 97% effective. This means three out of 100 people using depo provera will get pregnant each year.
If you have your injections on time (every 12 weeks) it can be more than 99% effective.
What will I notice?
Your bleeding may be irregular or prolonged, especially in the first three to six months. This is safe for your body and there are pills to stop this if it happens.
About 70% of people will have no periods after four injections. This is safe.
Can I still become pregnant after stopping the injections?
Your natural fertility can take some time to return to normal. On average this will be six months but it can take up to one year.
If you are planning a pregnancy soon it may be best not to use Depo Provera.
If you get pregnant while using Depo Provera, and decide to continue with your pregnancy, the chance of having an abnormal baby is not increased.
Who can use it?
Most people can use Depo Provera, even those who cannot use the combined contraceptive pill.
Who should not use it?
- If you have had breast cancer.
- If you are planning a pregnancy in the next few months you may prefer to use a different type of contraceptive.
What are the advantages?
- Almost 100% effective.
- Lasts for 12 weeks.
- No daily pill taking.
- Doesn’t interfere with sexual intercourse.
- No one else needs to know you are using it.
- Reduces the risk of endometrial cancer (cancer of the lining of the womb) by 80%.
- Helps if you have heavy or painful periods.
What are the disadvantages?
Once you have had an injection of Depo Provera, it lasts at least 12 weeks which can be a nuisance if you experience a side effect.
It can cause irregular or prolonged bleeding. This is more common on first starting to use Depo Provera and often improves with time.
Are there any possible side effects?
The research does NOT show that the injection causes any change in mood, libido or headaches.
Allergic reactions are possible but this is extremely rare.
Some people put on weight, some lose weight, most do not change weight
Depo Provera has been associated with a reduction in bone density. This improves after stopping Depo Provera.
The risk of endometrial cancer is reduced by 80%. There is no overall change in the rate of cancer of the cervix, the ovary or breast cancer.
Does the injection protect you from sexually transmissible infections (STIs)?
No. You need to use condoms (and lubricant) as well to protect against STIs.
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