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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.

OVERVIEW

_EFFICACY

99%+

_FREQUENCY

EVERY 5–10 YEARS

_{EFFECT ON FERTILITY}

UPON DISCONTINUATION OF USE, FERTILITY SHOULD RETURN TO NORMAL

_{BLOOD CLOT RISK}

NOT KNOWN TO INCREASE RISK

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.

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.

_{PERFECT USE^*}

99
^%
+

Effective

Approximately

1 out of every 100 women

in a year will experience an unintended pregnancy.

* Perfect use of a contraceptive method is when it is used correctly all the time.

_{TYPICAL USE^*}

99
^%
+

Effective

Approximately

1 out of every 100 women

in a year will experience an unintended pregnancy.

* Typical use is what generally happens in real life. It takes into account human error e.g. forgetting to take your pill. For the IUD, typical use is the same as perfect use.

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:

This is an illustrative example of a T shaped IUD. Different IUDs are available with a range of sizes to accommodate different uterus sizes.

1. T-shaped frame
Is composed of plastic. The arms of the T-shaped frame are folded away into the insertion tube whilst the IUD is being fitted. Once in the womb, the arms are unfolded.
2. Copper wire
Copper wire is wound around the vertical arm and sometimes the horizontal arm as well, depending on the type.
3. Removal threads
Two soft threads are attached to the base of the t-frame. These threads hang through the cervix into the top of the vagina. The threads are used to remove the IUD, if needed. It is not common for your partner to feel the threads during sex but if they can it shouldn’t cause any pain.

DOES THE IUD CONTAIN HORMONE?
No. The IUD is hormone free. Because it Is hormone free it does not stop ovulation or interfere with your normal hormonal cycle.
WHO CAN USE AN IUD?
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 undiagnosed abnormal uterine bleeding.
Have Wilson's disease (a disturbance of the body’s copper balance).
Have disturbances in blood clotting.
Have conditions associated with increased susceptibility to infections.
Have untreated cervical dysplasia.
Have cancer of the cervix or womb.
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.
An IUD may also not be the method of first choice if you are young or have not given birth.

PREPARING FOR YOUR GP APPOINTMENT

TALKING TO YOUR DOCTOR

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

LEARN MORE

PP-UN-WHC-GB-0289 July 2025

INTRAUTERINEDEVICE (IUD)

WHAT IS THE IUD?

OVERVIEW

EFFICACY

99%+

FREQUENCY

EVERY 5–10 YEARS

EFFECT ON FERTILITY

UPON DISCONTINUATION OF USE, FERTILITY SHOULD RETURN TO NORMAL

BLOOD CLOT RISK

NOT KNOWN TO INCREASE RISK

THE IUD IS A TYPE OF LONG-ACTING CONTRACEPTION

HOW DOES AN IUD WORK?

HOW EFFECTIVE IS THE IUD?

PERFECT USE*

99%+

TYPICAL USE*

99%+

WHY IS IT SO EFFECTIVE?

WHAT IS AN IUD MADE OF?

PREPARING FOR YOUR GP APPOINTMENT

TALKING TO YOUR DOCTOR

INTRAUTERINE

DEVICE (IUD)

_EFFICACY

_FREQUENCY

_{EFFECT ON FERTILITY}

_{BLOOD CLOT RISK}

_{PERFECT USE^*}

99
^%
+

_{TYPICAL USE^*}

99
^%
+