Intra Uterine Device (IUD)

The IUD is a small contraceptive device that is placed inside  the uterus. There are two kinds of IUD.

The copper IUD is a small plastic device with copper wrapped around its stem.

The progestogen IUD is a small T-shape device with a cylinder containing progestogen around its stem.

intra uterine device IUD

How does the IUD work?

Although the IUD has been used for more than 30 years to prevent pregnancy, how it works is still not fully understood. The IUD affects sperm movement and survival in the uterus (womb) so that they cannot reach the egg to fertilise it. The IUD also changes the lining of the womb (endometrium) so that it is not suitable for pregnancy and prevents an egg – if it does become fertilised – from developing.

How well does it work?

No contraception is 100 per cent effective but the IUD is 99.8 per cent effective.


Both the copper IUD and the progestogen IUD have the following benefits:

  • effective long term contraception (at least five years)
  • easy to maintain, you can't forget to use it as you might the Pill
  • it is cheaper than other contraception (more expensive at first but cheaper over the long term)
  • if you want to, you can try for pregnancy as soon as it is removed.

The progestogen IUD has the added benefit of reducing menstrual bleeding. This is a benefit for women who would normally have heavy or long lasting periods, or who have heavier or longer lasting periods with the copper IUD.


Both the copper and the progestogen IUD have the following disadvantages:

  • The IUD may expel itself from the uterus, usually during a period. You may not be aware that this has happened and should always check that the string is in place.
  • Although rare, when an IUD fails and a woman becomes pregnant, it must be removed as soon as possible. An IUD in a pregnant woman increases the risk of miscarriage.
  • There is a small risk of infection in the three weeks following insertion.
  • Because pelvic infections can lead to infertility, it is important you be particularly careful about protecting yourself from sexually transmitted infections.
  • The IUD may perforate the wall of the uterus. This is a very rare occurrence and may happen when the IUD is being inserted.
  • There is the risk of an ectopic pregnancy (where the fertilised egg implants in the fallopian tubes) when the IUD fails. This is very rare with the copper IUD and even rarer with the progestogen IUD.

The progestogen IUD can also have the following side effects:

  • Irregular bleeding or periods are likely in the first three to five months. Eventually you are likely to have very few periods at all.
  • It may cause a slight increase in the likelihood of vaginal dryness, flushing, headaches, nausea and acne.

The copper IUD may cause your periods to become heavier and more painful.

Who can use an IUD?

  • Women at low risk of contracting sexually transmitted infections.
  • Women who cannot or do not wish to take the Pill.

Who should not use an IUD?

  • Women who are at long term risk of contracting sexually transmitted infections (STIs) should not have an IUD fitted.
  • Women who have undiagnosed vaginal bleeding.
  • Women with pelvic inflammatory disease (PID).

Having an IUD fitted

Before you have an IUD fitted you should:

  • have a cervical screening test and swabs to rule out any pelvic infections
  • ensure that you are not pregnant (so either have the IUD inserted immediately after your period or use reliable contraception until it can be fitted).

How the IUD is fitted

You will be placed in the same position in the clinic as if you were about to have a cervical screening test. A speculum will be placed in your vagina and your cervix cleaned with an antiseptic. The length of the uterus is measured and the IUD is placed inside through the cervix or the opening to the uterus. The string is cut so that it is well up into the vagina. You or your sexual partner won't notice it but you should be able to feel the string if you reach right up into your vagina.

You will wait at the clinic for about 15 minutes to ensure that you feel no unnecessary discomfort or pain.

It is important that you do not have intercourse or use tampons for 48 hours following insertion to prevent infection.

What if I feel that something is wrong?

Contact your doctor when:

  • the string feels like it is shorter or longer than normal or you cannot feel the string at all. This means that the IUD may have shifted. It is important to check the length of string after each period
  • you experience persistent low back of abdominal pain, particularly when associated with a fever
  • you have an unusual discharge or bleeding or there is pain with intercourse
  • either you or your partner have had another sexual experience which increases your exposure to a sexually transmitted infection
  • six weeks after insertion and then when your regular cervical screening test is due.

Where to get more information

  • Your local doctor (GP)
  • Women's Health Clinics (at the Women's) on (03) 8345 3100.

Information about long acting reversible contraception (LARCs) including IUDs is also available in Arabic, Chinese, Hindi, Spanish, Urdu and Vietnamese – see Related Health Topics below


The Women’s does not accept any liability to any person for the information or advice (or use of such information or advice) which is provided on the Website or incorporated into it by reference. The Women’s provide this information on the understanding that all persons accessing it take responsibility for assessing its relevance and accuracy. Women are encouraged to discuss their health needs with a health practitioner. If you have concerns about your health, you should seek advice from your health care provider or if you require urgent care you should go to the nearest Emergency Dept.