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IUD (intrauterine device)

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What is an IUD?

An intrauterine device (IUD) is a small, T-shaped contraceptive device made from plastic and copper that fits inside the womb (uterus). It used to be called a coil or a loop.

It's a long-lasting and reversible method of contraception but it is not a barrier method. This means that an IUD can prevent pregnancy but won't stop you getting sexually transmitted infections (STIs). It's different to an intrauterine system (IUS) which releases the hormone progestogen into the body.

An IUD stops sperm from reaching the egg. It does this by releasing copper, which changes the make-up of the fluids in the womb and fallopian tubes. These changes prevent sperm from fertilising eggs. IUDs may also stop fertilised eggs from travelling along the fallopian tubes and implanting in the womb.

How do I get an IUD fitted?

There are different types and sizes of IUD to suit different women. IUDs need to be fitted by a trained doctor or nurse at your doctor surgery, local family planning clinic or sexual health clinic. You may need to be tested for infection before the fitting or you may be given antibiotics, in case of infection, to take as it's fitted.

It takes about 15 to 20 minutes to insert an IUD. The vagina is held open, like it is during a cervical smear test, and the IUD is inserted through the cervix and into the womb.

Some women find having an IUD fitted uncomfortable and painful, so you may also be offered painkillers. Read more about having an IUD fitted.

An IUD can stay in the womb for five to 10 years depending on the type. If you're 40 or over when you have an IUD fitted, it can be left in until you reach the menopause or until you no longer need contraception.

Most women can have an IUD fitted, including women who have never been pregnant or who are HIV positive. An IUD is usually fitted during your menstrual period. From the moment the IUD is fitted until the time it is taken out, you are protected against pregnancy.

Read more information on when an IUD can be used.

An IUD can be removed at any time by a trained doctor or nurse.

If you're not going to have another IUD put in and you don't want to become pregnant, use another contraceptive method (such as condoms) for seven days before you have the IUD removed. This is to stop sperm getting into your body. Sperm can live for seven days in the body and could cause pregnancy once the IUD is removed.

As soon as an IUD is taken out, your normal fertility should return.

How effective is an IUD?

An IUD is 98–99% effective at preventing pregnancy. Newer models that contain more copper are the most effective (over 99% effective). This means that less than one in every 100 women who use the IUD will get pregnant in a year.

As a long-lasting method of contraception, the IUD is very effective. You don't need to remember to take or use contraception to prevent pregnancy. However, there are some disadvantages to an IUD, such as longer and more painful periods. And you'll still need to use other types of contraception to prevent STIs. Read more about the things to consider before getting an IUD.

In rare cases there may also be some complications after having an IUD fitted. This can include pelvic infections in the first 20 days after fitting, or the IUD moving out of place. Read more about the risks of having an IUD fitted.

Emergency contraception

The IUD can also be used as a method of emergency contraception up to five days after unprotected sex or up to five days after the earliest time you could have released an egg (ovulation). If you have unprotected sex, make an appointment with your doctor or clinic as soon as possible.

IUD risks

Complications after having an IUD fitted are rare. Most complications will appear within the first year after fitting.


Longer or heavier periods can be a side effect of the IUD (particularly if you've always had heavy periods). For some people, this eases within a few months, but others continue to have longer and heavier periods.

If the problems continue, you may wish to consider an intrauterine system (IUS), which releases hormones that can reduce bleeding and pain.

The most common reasons for women having their IUD removed are vaginal pain and bleeding.

Pelvic infections

Pelvic infections can occur in the first 20 days after the IUD is fitted. The risk of infection from an IUD is extremely small. Less than one in 100 women who are at low risk of sexually transmitted infections (STIs) will get a pelvic infection.

Your doctor or clinician will usually recommend an internal examination before fitting an IUD to check that there are no existing infections.

See your doctor or clinician immediately if you get any pain in your lower abdomen or have a high temperature or smelly discharge in the first three weeks after your IUD is fitted. This may be pelvic inflammatory disease (PID), which can lead to infertility.


Occasionally the IUD is rejected by the womb (expulsion) or can move (displacement). This is more likely to happen soon after it has been fitted, although this isn't common. Your doctor or clinician will teach you how to check that your IUD is in place.

Damage to the womb

In very rare cases, an IUD can go through (perforate) the womb or neck of the womb (cervix) when it's put in. This can cause pain in the lower abdomen but doesn't usually cause any other symptoms. If the doctor or clinician fitting your IUD is experienced, the risk of this happening is extremely low.

If perforation occurs, you may need surgery to remove the IUD. Contact your doctor immediately if you feel a lot of pain after having an IUD fitted as perforations should be treated straight away.

Ectopic pregnancy

If the contraception fails and you become pregnant, your IUD should be removed as soon as possible if you're continuing with the pregnancy.

There's a small increased risk of ectopic pregnancy if a woman becomes pregnant while using an IUD.

Having an IUD fitted

Your doctor or clinician can advise you, based on your medical history, whether an IUD is the best method of contraception for you.

Before you have an IUD fitted, you will have an internal examination to determine the size and position of your womb. This is to make sure that the IUD can be positioned in the correct place.

You may also be tested for infection, such as sexually transmitted infections (STIs). It's best to do this before an IUD is fitted so that any infections can be treated. Sometimes, you may be given antibiotics at the same time as the IUD is fitted.

It takes about 15 to 20 minutes to insert an IUD. The vagina is held open, like it is during a cervical smear test, and the IUD is inserted through the cervix and into the womb.

The fitting process can be uncomfortable and sometimes painful. You may experience cramps afterwards.

You can ask for a local anaesthetic or painkillers, such as ibuprofen, before having the IUD fitted. Discuss this with your doctor or clinician beforehand. An anaesthetic injection itself can be painful, so many women have the procedure without one.

You may get period-like pain and bleeding for a few days after having an IUD fitted. This is normal. Painkillers before and after the procedure can ease this.


Once an IUD is fitted, it will need to be checked by a doctor after three to six weeks. Speak to your doctor or clinician if you have any problems after this initial check or if you want the device removed.

Also speak to your doctor or clinician if you or your partner are at risk of getting an STI. This is because STIs can lead to an infection in the pelvis.

Feeling unwell after having an IUD fitted

If you feel unwell, have pain in your lower abdomen, have a high temperature or a smelly discharge after having an IUD fitted, see your doctor or go back to the clinic where it was fitted as soon as you can. You may have an infection.

How to tell whether an IUD is still in place

Once fitted, an IUD has two thin threads that hang down a little way from your womb into the top of your vagina. The doctor or clinician who fits your IUD will teach you how to feel for these threads and check that the IUD is still in place.

Check your IUD is in place a few times in the first month after fitting, and then after each period or at regular intervals.

It's very unlikely that your IUD will come out, but if you can't feel the threads or if you think the IUD has moved, you may not be fully protected against pregnancy. See your doctor or clinician straight away and use extra contraception until your IUD has been checked. If you've had sex recently, you may need to use emergency contraception.


Your partner shouldn't be able to feel your IUD during sex. If he can feel the threads, get your doctor or nurse to check that your IUD is in place. If you feel any pain during sexual intercourse, go for a check-up with your doctor or clinician.

IUD advantages and disadvantages

Although an IUD is an effective method of contraception, there are some things to consider before having one fitted.

Advantages of an IUD

  • Most women can use an IUD, including women who have never been pregnant.
  • Once an IUD is fitted, it is immediately effective at preventing pregnancy for up to 10 years or until it's removed.
  • It doesn't interrupt sex.
  • It can be used if you're breastfeeding.
  • Your normal fertility returns as soon as the IUD is taken out.
  • It's not affected by other medicines.

There's no evidence that having an IUD fitted will increase the risk of cancer of the cervix, endometrium (lining of the womb) or ovaries. Some women experience changes in mood and libido, but these are very small.

Disadvantages of an IUD

  • Your periods may become heavier, longer or more painful, though this may improve after a few months.
  • You must have an internal examination to check whether an IUD is suitable for you, and another examination when it is fitted.
  • An IUD doesn't protect against sexually transmitted infections (STIs), so you may have to use condoms as well. If you get an STI while you have an IUD fitted, it could lead to a pelvic infection if left untreated.

The most common reasons that women stop using an IUD are vaginal bleeding and pain.

Who can use an IUD?

Most women can use an IUD, including women who have never been pregnant and those who are HIV positive. Your doctor or clinician will ask about your medical history to check if an IUD is the most suitable form of contraception for you.

You should not use an IUD if you have:

Women who have had an ectopic pregnancy or recent abortion, or who have an artificial heart valve, must consult their doctor or clinician before having an IUD fitted.

You should not be fitted with an IUD if there's a chance that you are already pregnant or if you or your partner are at risk of catching STIs.

The IUD is most appropriate for women with one long-term partner, who they're confident doesn't have any STIs. If you or your partner are unsure, go to your doctor or sexual health clinic to be tested for STIs.

Using an IUD after giving birth

An IUD can usually be fitted four to six weeks after giving birth (vaginal or caesarean). You'll need to use alternative contraception from three weeks (21 days) after the birth until the IUD is fitted. In some cases, an IUD can be fitted within 48 hours of giving birth.

An IUD is safe to use when you're [breastfeeding] and it won't affect your milk supply.

Using an IUD after a miscarriage or abortion

An IUD can be fitted after an abortion or miscarriage by an experienced doctor or nurse, as long as you were pregnant for less than 24 weeks. If you were pregnant for more than 24 weeks, you may have to wait a few weeks before having an IUD fitted.

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