A contraceptive injection that provides protection for two to three months.
The injection is usually given in your buttock by a trained person. It is not painful and only takes a few minutes. It can take up to seven days before the injection starts to work.
How good is the injection at preventing a pregnancy?
- The injection works very well at preventing a pregnancy.
- If one hundred women used the injection for a year and carried on with their normal sex life then only one of those women would fall pregnant during that period.
What are other good things about the injection?
- You can take it straight after an abortion.
- It can last up to either two or three months, depending on the injection. After each two or three months you will need to have another injection.
- It can help to reduce heavy periods.
- It does not interrupt sex.
What else should you know?
- If you decide you don’t want it any more you will have to wait two or three months, after you’ve had the injection, for its effects to end. For some women it may take a few more months for your fertility to return. Unlike condoms, it does not protect you from sexually transmitted infections.
Day to day life with your injection
- Your regular bleeding pattern may change while using the injection. For example, your periods may stop for a short while or your periods may be irregular for a few months. These changes are not serious and are short-term. Your health and long term fertility will be unaffected.
- Your injection will continue to work even if your bleeding pattern changes.
Frequently asked questions
- Does the injection cause weight gain or a fever or bleeding into the stomach?
Some women using the injection will gain a small amount of weight. Typically this will be 1-2kg per year. Other women using the injection may lose weight. The injection does not cause a fever or bleeding into the stomach.
- Can I still fall pregnant if I stop the injection?
Yes. The injection will not permanently end your fertility. Some women do not return to their pre-injection fertile state immediately when they stop the injection. It can be a couple of months before periods start again.
- Do I have to have follow up injections at exactly the right time?
If you want to rely on the injections as a means of contraception then it is important that you attend for a follow up injection at around the right time. It will still be effective if you are a couple of weeks early or late for your repeat injection. But you should not skip injections completely.