A woman can get pregnant if a man’s sperm reaches one of her eggs (ova). Contraception tries to stop this by keeping the egg and sperm apart or by stopping eggs being produced. One method of contraception is the intrauterine device, or IUD (sometimes called a coil).
IUD – what is it?
An IUD is a small T-shaped plastic and copper device that’s inserted into your womb (uterus) by a specially trained doctor or nurse.
The IUD works by stopping the sperm and egg from surviving in the womb or fallopian tubes. It may also prevent a fertilised egg from implanting in the womb.
The IUD is a long-acting reversible contraceptive (LARC) method. This means that once it’s in place, you don’t have to think about it each day or each time you have sex. There are several types and sizes of IUD.
You can use an IUD whether or not you’ve had children.
At a glance: facts about IUDs
- There are different types of IUD, some with more copper than others. IUDs with more copper are more than 99% effective. This means that fewer than one in 100 women who use an IUD will get pregnant in one year. IUDs with less copper will be less effective.
- An IUD works as soon as it’s put in, and lasts for five to 10 years, depending on the type.
- It can be put in at any time during your menstrual cycle, as long as you’re not pregnant.
- It can be removed at any time by a specially trained doctor or nurse and you’ll quickly return to normal levels of fertility.
- Changes to your periods (for example, being heavier, longer or more painful) are common in the first three to six months after an IUD is put in, but they’re likely to settle down after this. You might get spotting or bleeding between periods.
- There’s a very small chance of infection within 20 days of the IUD being fitted.
- There’s a risk that your body may expel the IUD.
- If you get pregnant, there’s an increased risk of ectopic pregnancy (when the egg implants outside the womb). But because you’re unlikely to get pregnant, the overall risk of ectopic pregnancy is lower than in women who don’t use contraception.
- Having the IUD put in can be uncomfortable. Ask the doctor or nurse about pain relief.
- An IUD may not be suitable for you if you’ve had previous pelvic infections.
- The IUD does not protect against sexually transmitted infections (STIs). By using condoms as well as the IUD, you’ll help to protect yourself against STIs.
How it prevents pregnancy
The IUD is similar to the IUS (intrauterine system) but works in a different way. Instead of releasing the hormone progestogen like the IUS, the IUD releases copper. Copper changes the make-up of the fluids in the womb and fallopian tubes, stopping sperm surviving there. IUDs may also stop fertilised eggs from implanting in the womb.
There are types and sizes of IUD to suit different women. IUDs need to be fitted by a trained doctor or nurse at your GP surgery, local contraception clinic or sexual health clinic.
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.
Having an IUD fitted
An IUD can be fitted at any time during your menstrual cycle, as long as you are not pregnant. You’ll be protected against pregnancy straight away.
Before you have an IUD fitted, you will have an internal examination to find out the size and position of your womb. This is to make sure that the IUD can be put in the correct place.
You may also be tested for infections, such as STIs. It’s best to do this before an IUD is fitted so that you can have treatment (if you need it) before the IUD is put in. 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 screening (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 get cramps afterwards. You can ask for a local anaesthetic or painkillers before having the IUD fitted. An anaesthetic injection itself can be painful, so many women have the procedure without.
You may get pain and bleeding for a few days after having an IUD fitted. Discuss this with your doctor or nurse beforehand.
The IUD needs to be checked by a doctor after three to six weeks. Speak to your doctor or nurse if you have any problems before or after this first check or if you want the IUD removed.
Speak to your doctor or nurse if you or your partner are at risk of getting an STI. This is because STIs can lead to an infection in the pelvis.
See your GP or go back to the clinic where your IUD was fitted as soon as you can if you:
- have pain in your lower abdomen
- have a high temperature
- have a smelly discharge
These may mean you have an infection.
How to tell whether an IUD is still in place
An IUD has two thin threads that hang down a little way from your womb into the top of your vagina. The doctor or nurse who fits your IUD will teach you how to feel for these threads and check that it is still in place.
Check your IUD is in place a few times in the first month, 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 getting pregnant. See a doctor or nurse straight away and use an extra method of contraception, such as condoms, 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. They may be able to cut the threads to a shorter length. If you feel any pain during sex, go for a check-up.
Removing an IUD
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 get pregnant, use another 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 up to seven days in the body and could make you pregnant once the IUD is removed.
As soon as an IUD is taken out, your normal fertility should return.
Who can use an IUD
Most women can use an IUD. This includes women who have never been pregnant and those who are HIV positive. Your doctor 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:
- an untreated STI or a pelvic infection
- problems with your womb or cervix
- 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 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. If you or your partner are unsure, go to your GP or a sexual health clinic to be tested.
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 straight away or within 48 hours 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.
- Most women can use an IUD, including women who have never been pregnant.
- Once an IUD is fitted, it works straight away and lasts 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, endometrial cancer (cancer of the lining of the womb) or ovarian cancer. There is no evidence that the IUD affects weight.
- Your periods may become heavier, longer or more painful, though this may improve after a few months.
- An IUD doesn’t protect against STIs, so you may have to use condoms as well. If you get an STI while you have an IUD, it could lead to a pelvic infection if not treated.
- Some women experience changes in mood and libido, but these changes are very small.
- The most common reasons that women stop using an IUD are vaginal bleeding and pain.
Complications after having an IUD fitted are rare. Most will appear within the first year after fitting.
Damage to the womb
In less than one in 1,000 cases, an IUD can perforate (make a hole in) 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 nurse fitting your IUD is experienced, the risk of this is very low.
If perforation occurs, you may need surgery to remove the IUD. Contact your GP straight away if you feel a lot of pain after having an IUD fitted as perforations should be treated immediately.
Pelvic infections can occur in the first 20 days after the IUD is fitted. The risk of infection is very small. Less than one in 100 women who are at low risk of STIs will get a pelvic infection.
Occasionally, the IUD is rejected (expelled) by the womb or can move (this is called displacement). This is more likely to happen soon after it has been fitted, although this is uncommon. Your doctor or nurse will teach you how to check that your IUD is in place.
If the IUD fails and you become pregnant, your IUD should be removed as soon as possible if you’re going to continue with the pregnancy. There’s a small increased risk of ectopic pregnancy if a woman becomes pregnant while using an IUD.
Where to get an IUD
Contraception is free to everyone through the NHS. Places where you can get contraception include:
- some GP surgeries – talk to your GP or practice nurse
- contraception clinics
- some young people’s services - call 0300 123 7123 for more information
If you’re under 16 years old
Contraception services are free and confidential, including for people under the age of 16.
If you’re under 16 and want contraception, the doctor, nurse or pharmacist won’t tell your parents (or carer) as long as they believe you fully understand the information you’re given, and your decisions.
Doctors and nurses work under strict guidelines when dealing with people under 16. They’ll encourage you to consider telling your parents, but they won’t make you.
The only time that a professional might want to tell someone else is if they believe you’re at risk of harm, such as abuse. The risk would need to be serious, and they would usually discuss this with you first.