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Intrauterine devices (IUDs) for contraception

Key points about intrauterine devices (IUDs) for contraception

The intrauterine device, or IUD, is a form of contraception.
Intrauterine devices (IUDs) for contraception are also called IUCD, 'the coil', 'loops', Mirena® and Jaydess®.
Find out how an IUD is used to prevent pregnancy and possible side effects.

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The intrauterine device, or IUD, is a form of contraception for women, to prevent pregnancy. An IUD is also commonly called an intrauterine contraceptive device (IUCD), 'the coil’ or ‘loops’.

An IUD is a small, T-shaped plastic device that's put into your uterus (womb) and has a thread tied to the end which hangs down through the cervix into the vagina.
It's a long-acting form of contraception, which means that once it's put in you don't have to remember about it every day or every time you have sex.
Its effect is reversible which means that your natural fertility returns when the IUD is removed.

Types of IUD

In Aotearoa New Zealand there are 2 types of IUD:

hormonal IUDs containing progestogen (Mirena®, Jaydess®)
copper IUDs.

Hormone or progestogen IUD
The hormonal IUD contains a progestogen called levonorgestrel that's slowly released into your womb (uterus).

Progestogen prevents pregnancy by making the mucus in your cervix thicker so sperm can’t travel through it to get to your egg. It also affects the lining of the uterus, making it unsuitable for a fertilised egg to implant and grow.

Progestogen hormones in IUDs also reduce menstrual bleeding and cramping. Because of this, it’s often used to treat menorrhagia (heavy periods).

Examples of the hormonal or progestogen-only IUD are Mirena® and Jaydess®.

Mirena® is effective for 5 years, while Jaydess® is effective for 3 years. At the end of this time, your IUD will need to be replaced with a new one if you're using it for contraception.

Copper IUD
The copper IUD works by releasing tiny amounts of copper into your womb which damages or kills the sperm, and also affects the lining of the uterus, making it unsuitable for a fertilised egg to implant and grow.

The copper IUD is generally effective for 5 years and is usually changed 5 years after insertion.
Your healthcare provider will advise you if your IUD can be left for longer.
The copper IUD can be used as emergency contraception. Read more about emergency contraception.

Pros	Cons
✔ You don’t have to remember to take a tablet every day – IUDs can last for 3 to 5 years. ✔ It's highly effective and reliable for preventing pregnancy. ✔ It's reversible – you can choose to have it taken out at any time. ✔ The hormonal IUD can help you with heavy menstrual bleeding or painful periods. ✔ It doesn't affect breastfeeding. ✔ It doesn’t interfere with having sex in the way that physical barrier methods do. ✔ It may reduce the risk of endometrial cancer.	✘ It may cause irregular bleeding, more bleeding or cramping initially, but this gets better over time. ✘ It may cause pain, cramps or dizziness when the IUD is put in or taken out. ✘ It has a small risk of infection and a very small risk of damage to your womb when it's put in. ✘ Although the chance of it happening is rare, it can come out by itself. You will be taught how to feel and check the threads are still in the right place. ✘ It doesn't protect against sexually transmitted infections STIs, so it’s important to use condoms when you have sex with new partners or people whose sexual history you don't know.

Pros

Cons

✔ You don’t have to remember to take a tablet every day – IUDs can last for 3 to 5 years.

✔ It's highly effective and reliable for preventing pregnancy.

✔ It's reversible – you can choose to have it taken out at any time.

✔ The hormonal IUD can help you with heavy menstrual bleeding or painful periods.

✔ It doesn't affect breastfeeding.

✔ It doesn’t interfere with having sex in the way that physical barrier methods do.

✔ It may reduce the risk of endometrial cancer.

✘ It may cause irregular bleeding, more bleeding or cramping initially, but this gets better over time.

✘ It may cause pain, cramps or dizziness when the IUD is put in or taken out.

✘ It has a small risk of infection and a very small risk of damage to your womb when it's put in.

✘ Although the chance of it happening is rare, it can come out by itself. You will be taught how to feel and check the threads are still in the right place.

✘ It doesn't protect against sexually transmitted infections STIs, so it’s important to use condoms when you have sex with new partners or people whose sexual history you don't know.

IUDs are a very reliable form of contraception.

Both the progestogen and copper IUDs are at least 99% effective in preventing pregnancy. This means that fewer than 1 out of every 100 women using an IUD will get pregnant each year.

Most pregnancies that occur with an IUD happen because the IUD is pushed out of the uterus without the person noticing. This is most likely to happen:

if you have heavy or painful periods
if you have a high body mass index (BMI)
if the IUD is put in just after giving birth or an abortion
if you haven't had a baby.

Once in place, a copper IUD is effective as a contraceptive straight away.

If you’ve had a progestogen hormonal IUD put in within 7 days of the start of your period it’s effective as a contraceptive straight away. Otherwise you’ll need to use additional contraception for 7 days before you’re safe from pregnancy.

The IUD can be put in at any time but you should only have an IUD put in if you're sure you’re not pregnant and you don’t have a sexually transmitted infection such as chlamydia or gonorrhoea.

The IUD is usually put in towards the end of a period or shortly afterwards, to ensure you’re not hapū. You can also get one 4 to 6 weeks after your pēpi is born or straight after an abortion.

Before the IUD is put in, you'll need to have a vaginal examination. The doctor or nurse will check the size and position of your womb (uterus).

The IUD is then put in using a small plastic device.

Putting an IUD in can sometimes be uncomfortable. Read more about discomfort or pain during the insertion of an IUD.
Light vaginal bleeding may also occur for a short while afterwards. Use pads rather than tampons or menstrual cups for the first few days after your IUD is put in.
It’s also recommended to avoid sex, swimming and baths for the first few days after a progestogen hormonal IUD is put in.
Your healthcare provider will usually want to check that there are no problems a few weeks after putting in an IUD. This is best done after your next period. After this, there's no need for any routine check until it is time to remove the IUD. However, contact your healthcare provider at any time if you have any problems or queries.
Most people have no problems, and the IUD can remain in place for several years.

Read more about intrauterine devices (IUDs)(external link) including how to prepare for your appointment and what to expect after your IUD appointment.

Checking the IUD is in place

The IUD can come out of your uterus (also called expulsion): In a small number of people, the IUD may come out of your uterus. The risk is higher in teenagers, women with heavy menstrual bleeding, women with a high body mass index (BMI) and women who have an IUD put in immediately after childbirth. If the IUD comes out, it's no longer effective. You may be able to have a new IUD put in.
You’ll be taught how to feel for the threads of the IUD so you can check it’s in place.
It’s best to check the threads regularly, after each period or at the beginning of each calendar month.
If you can’t feel the thread, it doesn't necessarily mean that the IUD has fallen out. Sometimes the thread is just difficult to feel or has been pulled up into the cervical canal (which won’t harm you).
Contact your healthcare provider if you can’t feel the IUD thread.

Other information

Other medicines: The levonorgestrel in the hormonal IUD interacts with some medicines (eg, anti-seizure medicines such as carbamazepine, lamotrigine or HIV medicines), herbal supplements (eg, St John’s Wort) and rongoā Māori, so check with your healthcare provider before starting any new medicines or supplements.
Replacement: The IUD works for a maximum of 3 to 5 years for contraception depending on which type you have.
Pregnant: If you become pregnant, contact your healthcare provider.
Sexually transmitted diseases: the IUD doesn't protect you from sexually transmitted infections (STIs).
Removal: The IUD can be taken out at any time if you’d like it removed. This needs to be done by a trained healthcare provider.
After removal: Once the IUD is removed there’s an almost immediate loss of contraceptive effect. You’re at risk of getting pregnant if you’ve had sex in the week before the removal and immediately after. If you don’t want to become pregnant, you must use another form of contraception for 7 days before and straight after the IUD is removed.

Any pain or discomfort during and after an IUD is put in or removed is different for everyone.

If you’re worried about pain or discomfort it’s a good idea to talk to your healthcare provider beforehand to discuss your options.

You can take a support person with you during the insertion and removal of the IUD.

When the IUD is put in

Most people feel some discomfort or pain. The type of IUD (hormonal or copper), your pain tolerance, and whether you’ve given birth before can influence how painful it feels.

The pain might feel like cramping or a sharp pinch that lasts for a few minutes. Some compare it to a strong period cramp.

To help reduce pain during the procedure, your healthcare provider may suggest taking over-the-counter pain relievers such as paracetamol and ibuprofen about one hour before the procedure.

It’s important to tell your healthcare provider if you’re having pain during the procedure.

Video: IUD insertion and pain - what to expect with Dr McNamee

(Sexual Health Victoria, Australia, 2023)

After the IUD is put in

It's common to experience cramping after the IUD has been put in. In some people the cramps may be mild and go away within a few hours. Others may have stronger period-like cramps for a few days afterwards.

The cramps can vary, and they usually lessen over time. You can use pain relievers such as paracetamol and ibuprofen. A hot water bottle or heat pad may also help.

If you have a sudden and severe attack of pain or any continuous lower abdominal pain, you should seek medical advice.

During removal of the IUD

The pain level when removing an IUD can also vary from person to person. Some people get mild discomfort or cramping during the procedure, while others might feel stronger pain.

The removal usually only takes a few minutes, and while it may feel uncomfortable, it's generally quick.

Some people may be advised to take pain relief before the procedure to help manage discomfort. In rare cases, if the IUD is difficult to remove or embedded, it might require additional steps, which can be uncomfortable.

Like all medicines, the IUD can cause side effects, although not everyone gets them.

Side effects	What should I do?
Pain, cramps Light bleeding Dizziness Feeling weak	This can occur after an IUD is put in. If these symptoms continue for more than a few days, contact your healthcare provider.
Irregular bleeding Heavier or lighter periods Bleeding or spotting in between your periods	These are very common. They usually happen in the first few weeks or months after the IUD is put in and often settle with time. If these bother you, tell your healthcare provider.
Signs of infection such as severe pain in the tummy area, fever, flu-like symptoms, feeling unwell, dizziness, feeling faint or vaginal discharge	There is a small risk of infection especially within the first 20 days after insertion. Tell your healthcare provider immediately or ring Healthline 0800 611 116.