Better Health Channel
The Victoria (Australia) state government provides online consumer-focused health and medical information.
Intrauterine contraceptive device (IUD, IUCD)
An IUD is used to prevent pregnancy. You can get copper IUDs or hormonal IUDs (Mirena). These sit inside your uterus (womb). Nylon threads attached to the IUD hang down into your vagina.
An IUD works by preventing fertilisation of the egg. The copper or hormone stops sperm moving through the uterus towards the egg. Occasionally this doesn’t work and an egg is fertilised. The IUD then stops this egg implanting into the uterus.
- The copper IUD is 99 percent effective in preventing pregnancy.
- Mirena is 99.9 percent effective in preventing pregnancy.
An IUD is usually recommended for women over 25 who have had a baby.
Advantages of an IUD
- It can stay in place for five years or more.
- It’s possible to get pregnant as soon as the IUD is removed.
- It doesn’t interfere with sexual intercourse.
- The IUD is safe to use if you’re breastfeeding.
- It’s safe to use if you can’t take the pill.
- With Mirena, most women have lighter periods and less period pain. Some women may have no periods at all.
- The copper IUD has no hormonal side-effects.
Disadvantages of an IUD
- The IUD will not protect you from sexually transmitted diseases.
- You have a greater chance of getting an infection when using an IUD. For this reason, women with more than one sex partner should consider another form of birth control.
- You shouldn’t use an IUD if you have unusual vaginal bleeding, an abnormal cervical smear, an infection, or are pregnant.
- With the copper IUD, there can be increased bleeding and cramping during periods.
- There’s a higher risk of having an ectopic (tubal) pregnancy if you get pregnant when an IUD is in place.
- Copper can cause an allergic reaction, but this is very rare. Don’t use the copper IUD if you’re allergic.
- Some women may notice hormonal side-effects from using Mirena.
Getting an IUD
If you decide that an IUD is the right contraception for you, you’ll need to see your doctor or a Family Planning clinic.
The IUD is put into your uterus through your cervix. The procedure takes a few minutes and may be painful.
- Following the placement of an IUD into the uterus, you may have some cramps for a couple of hours and some spotting, which could last for up to two weeks. You may also have heavy periods. This is not as common with the hormone type of IUD (Mirena).
- To reduce the risk of infection after the insertion, you should use sanitary pads (not tampons) for the first 48 hours, and do not have sex in that time.
The best time to fit an IUD is:
- during or just after a menstrual period
- six weeks after your baby is born
- immediately after an abortion.
An IUD can also be used as an emergency contraception method after unprotected sex.
As a safety precaution, after every period you should check for the string attached to your IUD, to make sure it’s still properly in place. It’s also a good idea to do this one week after your IUD has been put in.
When to see your doctor
If you have an IUD, you should see your doctor if you have any of these symptoms:
- severe cramping
- unusual bleeding
- fever without another cause
- bad-smelling discharge
- late period.
You should also see your doctor if you can feel the hard plastic of the IUD or if you can’t feel the string.
Call Healthline 0800 611 116 if you are unsure what you should do.
Removing your IUD
If you think you might be pregnant, see your doctor to get your IUD removed as soon as possible. There’s an increased chance of miscarriage if the IUD is left in place while you’re pregnant.
If you decide you want your IUD removed, the best time is during your period. Your doctor removes the IUD by pulling the threads. This may be painful for a few seconds.
For more information, contact your doctor or Family Planning.