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Contraceptive injection

Contraceptive injection


Other names: hormonal method


what is the contraceptive injection?

The contraceptive injection is given as an injection into your bottom, thigh, upper arm or stomach and releases hormone into your bloodstream to prevent pregnancy.


It is a highly effective form of contraception and can last 8, 12 or 13 weeks depending on the type.

Contraceptive injection


The injection is a type of long-acting contraception


The injection fits into the category of long-acting contraception. It is long acting because it can provide contraception for a long period of time - up to 8-13 weeks.


Learn more about long acting contraception

How does the contraceptive injection work?

The contraceptive injection steadily releases a progestogen hormone into your bloodstream, which:


Stops the ovaries from releasing an egg each month (ovulation).


Thickens the cervical mucus to make it harder for sperm to move through the cervix.

how effective is an injection at preventing pregnancy?

The contraceptive injection is 94% effective at preventing pregnancy with typical use. This is because there is a chance that the injection can be incorrectly administered or administered late. With perfect use it is 99% effective.





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Approximately 1 out of every 100 women in a year will experience an unintended pregnancy.




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Approximately 6 out of every 100 women in a year will experience an unintended pregnancy.

What is the injection made of?

The contraceptive injection is an off-white suspension of a progestogen hormone (a synthetic version of the hormone progesterone). The contraceptive injection can be administered by a healthcare professional or alternatively self-administered, depending on the type you choose.

    Yes. The contraceptive injection contains a progestogen hormone called medroxyprogesterone acetate or norethisterone enantate, which is released throughout the entire body.


    It is similar to the hormone progesterone made naturally by your ovaries.


    The implant does not contain oestrogen.

    The contraceptive injection can be used in most women. In adolescents it may be used, but only after ther methods of contraception have been discussed and are considered unsuitable or unacceptable.


    The contraceptive injection might not be suitable if you:


    • Think you might be pregnant.


    • Do not want your periods to change.


    • Want to have a baby in the next year.


    • Have unexplained bleeding in between periods or after sex.


    • Have breast cancer or have had it in the past.


    • Have arterial disease or a history of heart disease or stroke.


    • Have liver disease.


    • Are at risk of osteoporosis.

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    Talking to your doctor

    Get the information you need for an informed discussion with your doctor.


    Learn more

    PP-UN-WHC-GB-0076 September 2023


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