Page last reviewed: 13/07/2011

An 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 is a long-lasting and reversible method of contraception but it is not a barrier method. This means that an IUD cannot stop you getting sexually transmitted infections (STIs).

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 GP surgery or local family planning clinic.

They can stay in the womb for five to 10 years depending on the type. If you are 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.

How it works

An IUD stops sperm from reaching the egg. It does this by releasing copper into the body, 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 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 do not need to remember to take or use contraception to prevent pregnancy. However, it does not protect you against STIs.

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 GP or clinic as soon as possible.




The uterus (or womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.

Page last reviewed: 13/07/2011

Most women can use an IUD, including women who have never been pregnant and those who are HIV positive. Your GP or nurse 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:

  • any untreated sexually transmitted infections (STIs) or pelvic infection,
  • problems with your womb or cervix, or
  • any unexplained bleeding from your vagina, for example between periods or after sex.

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

You should not be fitted with an IUD if there is a chance 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 are confident does not have any STIs. If you or your partner are unsure, go to your GP or sexual health clinic to be tested for STIs.

Using an IUD after giving birth

An IUD is usually fitted four to six weeks after the birth (vaginal or caesarean). You will 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 are breastfeeding and will not 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.


The uterus (or womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.
Ectopic refers to a pregnancy that occurs outside the womb, most commonly in the fallopian tubes.
An abortion or termination is a medical procedure that ends pregnancy. The method used depends on the stage of pregnancy.
A caesarean section is an operation to deliver a baby by cutting through the mother's abdomen to open the womb.

Page last reviewed: 13/07/2011

Your GP or nurse 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 any infections, such as sexually transmitted infections (STIs). It is 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 an 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, especially if you have not had children and your cervix is not stretched. 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 GP or nurse 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, and 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 GP or nurse if you have any problems after this initial check or if you want the device removed.

Also speak to your GP or nurse if you or your partner are at risk of getting an STI as 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 GP or go back to the clinic where it was fitted as soon as you can. You may have an infection.

How to tell that 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 GP or nurse 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 is very unlikely that your IUD will come out, but if you cannot feel the threads or if you think the IUD has moved, you may not be fully protected against pregnancy. See your doctor or nurse straight away and use extra contraception until your IUD has been checked. If you have had sex recently, you may need to use emergency contraception.


Your partner should not be able to feel your IUD during sex. If he can feel the threads, get your GP 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 GP or nurse.


Smear test
During a cervical screening test, a sample of cells from a woman's cervix is taken and examined for abnormalities.
Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.
The uterus (or womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Anaesthetic is a drug used to either numb a part of the body (local) or to put a patient to sleep (general) during surgery.
Painkillers or analgesics are medicines that relieve pain. Examples include paracetamol, aspirin and ibuprofen.

Page last reviewed: 13/07/2011

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

If you are not going to have another IUD put in and you do not 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.

If you want to start trying for a baby after removing an IUD, ask your GP or nurse for advice beforehand. You may want to start taking folic acid, look at ways to stop smoking ( and cut down on alcohol to improve your chances of conceiving and having a healthy pregnancy.

Page last reviewed: 13/07/2011

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 and will be for up to 10 years or until it is removed.
  • It does not interrupt sex.
  • It can be used if you are breastfeeding.
  • Your normal fertility returns as soon as the IUD is taken out.
  • It is not affected by other medicines.

There is no evidence that IUDs affect body weight or 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 have to have an internal examination to check whether an IUD is suitable for you and another one when it is fitted.
  • An IUD does not 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 it is not treated.

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

Page last reviewed: 13/07/2011

Most complications with IUDs happen in the first year after fitting.

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 will get a pelvic infection.

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

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, see your GP immediately. Pelvic inflammatory disease (PID) can lead to infertility.


Occasionally the IUD is rejected by the womb (expulsion) or can move (displacement). This is not common and is more likely to happen soon after it has been fitted. Your doctor or nurse will teach you how to check that your IUD is in place.


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

If perforation does occur, you may need surgery to remove the IUD. Contact your GP immediately if you experience a lot of pain after having an IUD fitted as perforation 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 are continuing with the pregnancy.

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


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

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



Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.


Ectopic refers to a pregnancy that occurs outside the womb, most commonly in the fallopian tubes.


The uterus (or womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.


Ovaries are the pair of reproductive organs that produce eggs and sex hormones in women.


Discharge is when a liquid, such as pus, oozes from a part of your body.

Content provided by NHS Choices and adapted for Ireland by the Health A-Z.

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