The IUD is over 99% effective. Fewer than 1 in 100 IUD users will get pregnant in 1 year. When the IUD is used for 5 years, fewer than 2 in 100 IUD users will get pregnant over 5 years.

If 100 sexually active women don’t use any contraception 80 to 90 will get pregnant in a year.

The IUD is a method of long-acting reversible contraception (LARC). LARC is very effective because it doesn’t depend on you remembering to take or use it.

See our guide to long-acting reversible contraception.

The copper in the IUD prevents sperm from surviving, and alters your cervical mucus to prevent sperm from reaching an egg.

An IUD may also work by stopping a fertilised egg from implanting in the uterus.

An IUD doesn’t cause an abortion.

You can go to a contraception or sexual health clinic or to a doctor or nurse at a GP surgery.

An IUD can only be fitted by a trained doctor or nurse so not all doctors and practice nurses will be able to fit IUDs.

It may not always be possible to fit the IUD at your first visit, you may need a follow up appointment.

Most people with a uterus can use an IUD, including those who’ve never been pregnant, young people, and people who are HIV positive.

Your doctor or nurse will need to ask you about your medical history to check if the IUD is suitable for you.

Do mention any illnesses or operations you’ve had as you may require specialist care when the IUD is fitted.

Some conditions which may mean you shouldn’t use an IUD are that you:

• think you might already be pregnant
• have an untreated sexually transmitted infection or pelvic infection
• have problems with your uterus or cervix
• have unexplained bleeding from your vagina (for example, between periods or after sex)

What are the advantages?

• It works as soon as it’s put in
• It works for 5 or 10 years, depending on type
• It can be used if you’re breastfeeding
• It’s not affected by other medicines
• Your fertility returns to normal as soon as the IUD is taken out

What are the disadvantages?

• Your periods may be heavier, longer or more painful. This may improve after a few months
• You’ll need an internal examination when the IUD is fitted
• The IUD doesn’t protect you from sexually transmitted infections, so you may want to use condoms as well
• The IUD doesn’t increase your risk of infection, but if you get an infection when an IUD is in place this could lead to a pelvic infection if it isn’t treated

• There’s a small chance of you getting an infection during the first few weeks after an IUD is put in. You may be advised to have a check for sexually transmitted infections before an IUD is fitted or at the time it’s fitted.

• The IUD can be pushed out (expulsion) by your uterus (womb) or it can move (displacement). This isn’t common. It’s more likely to happen soon after the IUD has been put in and you may not know it’s happened. Your doctor or nurse will teach you how to check the threads so you know the IUD is in place.

• It isn’t common, but there’s a very small risk that the IUD might go through (perforate) your uterus or cervix when it’s put in. The risk is higher if you’ve recently given birth or are breastfeeding. This may cause pain but often there are no symptoms and the uterus or cervix will heal by itself. The risk of perforation is low when an IUD is fitted by an experienced doctor or nurse. If it does happen, the IUD may have to be removed by surgery.

• You’re unlikely to get pregnant while using an IUD but if you do, there’s a risk of having an ectopic pregnancy. You’re less likely to have an ectopic pregnancy while you’re using a copper IUD than when you’re not using any contraception.

A copper IUD can be put in at any time in your menstrual cycle, if it’s certain you’re not pregnant.

It’s effective immediately. It can also be used as emergency contraception – see below.

You may be able to have an IUD fitted at the time of vaginal delivery or caesarean section.

If an IUD isn’t fitted in the first 48 hours after you give birth, you need to wait until 4 weeks after the birth.

You’ll need to use another method of contraception from 3 weeks (day 21) after the birth until the IUD is put in.

An IUD can be used safely while you’re breastfeeding and won’t affect your milk supply.

An IUD can be put in by an experienced doctor or nurse immediately after a miscarriage or abortion. You’ll be protected from pregnancy straight away.

The IUD is inserted into your uterus (womb).

A doctor or nurse will examine you internally to find the position and size of your uterus before they put in an IUD.

Sometimes they’ll check for any existing infections. This can be done before or at the time of fitting the IUD. Sometimes you may be given antibiotics at the same time the IUD is fitted.

Your appointment will last around 20 to 30 minutes.

Inserting the IUD usually takes around 5 minutes. It can be uncomfortable or painful for some people and you may be offered a local anaesthetic.

Your doctor or nurse should talk to you about this beforehand.

You may get a period-type pain and some light bleeding for a few days after the IUD is fitted. Pain-relieving drugs can help with this.

If you feel unwell and have pain in your lower abdomen, with a high temperature or a smelly discharge from your vagina, see a doctor or go back to the clinic where the IUD was fitted as soon as possible. You may have an infection.

Yes, it’s safe to use tampons or a menstrual cup. Take care not to pull on the IUD threads when you’re removing tampons or a menstrual cup.

An IUD has two threads attached to the end that hang a little way down from your uterus (womb) into the top of your vagina.

The doctor or nurse will teach you how to feel the threads to make sure the IUD is still in place.

You should do this a few times in the first month and at regular intervals, for example after your period.

It’s very unlikely that an IUD will come out, but if you can’t feel the threads, or if you think you can feel the IUD itself, you may not be protected from pregnancy. If this happens, see your doctor or nurse straight away and use an extra contraceptive method, such as condoms. If you had sex recently you might need to use emergency contraception – see below.

Rarely, a partner may say they can feel the threads during sex. If this happens, ask your doctor or nurse to check the threads.

You may have spotting (bleeding between periods) or irregular bleeding in the first six months after you’ve had a copper IUD fitted.

Some women have heavier, longer and more painful periods. This may improve over time. If you have prolonged bleeding the doctor or nurse may be able to give you a medicine that can help control the bleeding.

They may also check the bleeding isn’t due to other causes such as infection. If you already have very heavy or painful periods, an IUD may not be the best choice.

You may wish to consider a hormonal IUD. It releases a progestogen hormone which can reduce bleeding and pain.

A trained doctor or nurse can take the IUD out at any time by pulling gently on the threads.

If you want to carry on using an IUD, the doctor or nurse can put in a new one at the same time. You’ll continue to be protected from pregnancy.

If you want to stop using the copper IUD, go back to the doctor or nurse and ask for it to be taken out.

Your periods and fertility will return to normal as soon as the IUD is removed.

If you don’t want to get pregnant you need to use additional contraception, such as condoms, or avoid sex for seven days before the IUD is taken out.

You’ll also need to use another method of contraception from the day the IUD is removed.

If you want to try for a baby, start pre-pregnancy care such as taking folic acid and stopping smoking. Ask your doctor or nurse for advice.

The copper IUD is highly effective contraception and it’s unlikely you’ll get pregnant.

If you do get pregnant there’s a small increased risk it will be an ectopic pregnancy. An ectopic pregnancy develops outside the uterus, usually in a fallopian tube.

If you think you might be pregnant and/or you have a sudden or unusual pain in your lower abdomen, seek medical advice as soon as possible. This might be the warning sign of an ectopic pregnancy.

If you’re pregnant, speak to your doctor or nurse as soon as possible. If you want to continue the pregnancy, they will talk to you about removing the IUD. If it’s early in the pregnancy it’s usually recommended to remove it as soon as possible. The doctor or nurse will discuss the benefits and risks with you.

You should have your IUD checked 3 to 6 weeks after it’s put in.

An IUD works for contraception for 5 or 10 years depending on the type.

If it’s fitted when you’re aged 40 or over, it works for contraception until after the menopause when contraception isn’t needed.

Contact your doctor or nurse if you have any problems, questions or want the IUD removed.

It’s important to seek advice if you think you could be at risk of getting a sexually transmitted infection, as this can lead to a pelvic infection.