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Intrauterine Device (IUD)

Intrauterine Device (IUD)


Other names: non-hormonal coil; copper coil


what is the IUD?

The IUD, also called the copper coil, is a small copper and plastic T-shaped device that is placed in your uterus (womb) and releases copper to prevent pregnancy.


It is a highly effective contraceptive and lasts up to 5-10 years depending on the type you choose.



The IUD is a type of long-acting contraception


The IUD belongs to a category of contraceptives called LARCs (long-acting reversible contraceptives). The IUD provides contraception for a long period of time - up to 10 years (long acting). It can also be removed at any point if your plans change and you will return to your normal level of fertility once it is removed (reversible).

How does an IUD work?


Copper in the IUD immobilises sperm which makes it more difficult for sperm to reach and fertilise the egg.


On the rare occasion a sperm does get through, the copper stops a fertilized egg from implanting itself to the lining too.

How effective is the IUD?

At 99%, it’s one of the most effective contraceptive methods. An IUD is over 99% effective preventing pregnancy with both perfect use and typical use, meaning that less than 1 in 100 women will get pregnant every year if they have an IUS.





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




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


Among 100 women who use no birth control and regularly have sex, it is expected that about 85 will become pregnant in a year.

Why is it so effective?

It’s a very effective option because once fitted by a healthcare professional, the IUD doesn’t rely on you having to remember to take it for it to work.

What is an IUD made of?

There are three parts to the IUD:

T-shaped frame Copper wire Removal threads

    No. The IUD is hormone free. Because it Is hormone free it does not stop ovulation or interfere with your normal hormonal cycle.

    The IUD is not suitable for everyone. To find out whether the IUD is right for you, talk to a GP, nurse or pharmacist.


    The IUD may not be suitable if you:


    • Are or think you might be pregnant.


    • Have an untreated sexually transmitted infection (STI) or a pelvic infection.


    • Have had an infection or inflammation of your womb following delivery or abortion, during the last 3 months.


    • Have problems with your womb or cervix e.g. fibroids.


    • Have unexplained bleeding between periods or after sex.


    • Suffer from heavy menstrual bleeding.


    • People who have had an ectopic pregnancy or who have an artificial heart valve must consult their GP or clinician before having an IUD fitted.

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    Talking to your doctor

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


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    PP-UN-WHC-GB-0074 September 2023


    The health information on this site has been reviewed and approved by Bayer by an appropriately qualified medical reviewer. It is intended as general information only. It is not intended to replace a consultation with a healthcare professional, to provide specific medical advice or replace the patient information leaflet provided with your medicine. Treatments discussed here should be initiated under medical supervision. For full information including side effects and eligibility for treatment, please consult your healthcare professional. Always speak to your doctor or nurse for personal medical advice.


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