An intrauterine device (IUD) is a small contraceptive device that is put into the uterus (womb) to prevent pregnancy. The two types available in Australia are the copper IUD and the hormonal IUD (MirenaTM
). The hormonal IUD contains progestogen, which is a synthetic version of the hormone progesterone that women make naturally. Both types are among the most effective methods of contraception and can stay in place for at least five years.
IUDs affect the way sperm move and survive in the uterus, stopping these cells from reaching and fertilising the ovum (egg). IUDs can also change the lining of the uterus to stop a fertilised ovum from sticking. The hormonal IUD can make the fluid at the opening to the uterus thicker, stopping sperm from getting through. It can also affect ovulation by changing the hormones that cause an ovum to be released each month.
When choosing the method of contraception that best suits you, it can help to talk to a doctor or nurse about your options. Different methods may suit you at different times in your life. A doctor or nurse can give you information about the benefits and risks of using the copper or hormonal IUD, as well as other methods of contraception. Other methods include the contraceptive implant or injection, the vaginal ring or the combined oral contraceptive pill.
The copper IUD is a small plastic device with copper wire wrapped around it and a fine nylon thread attached to the end. When the device is in place, the thread comes out through the cervix (entrance to the uterus) into the top of the vagina. This piece of thread lets you check that the IUD is still in place and makes it easy for a doctor to take it out. You cannot feel the thread unless you put your finger deep inside your vagina.
The hormonal IUD (MirenaTM
) is a small plastic T-shaped device that contains progestogen. This is a synthetic version of the hormone progesterone that women make naturally. The device has a coating (membrane) that controls the release of progestogen into the uterus. Like the copper IUD, it has a fine nylon thread attached to the end to make checking and taking it out easier.
Advantages of IUDs
Advantages of using the copper or hormonal IUD include:
- Both the copper and hormonal IUD are more than 99 per cent effective in preventing pregnancy.
- Both types last between five and ten years.
- Once it has been put in, you will only need to check the thread each month.
- The device can be taken out at any time by a specially trained doctor or nurse.
- Your chance of getting pregnant will go back to normal as soon as the copper or hormonal IUD has been taken out.
Disadvantages of IUDs
Disadvantages of using the copper or hormonal IUD include:
- Both types need to be put in by a specially trained doctor or nurse.
- You may have extra costs and difficulty accessing the service.
- There is a small risk of infection at the time the IUD is put in and for the first 3 weeks.
- There is a small risk of perforation, which is when the IUD makes a hole in the wall of the uterus when it is put in.
- If the IUD does not work and you get pregnant, there may be complications with the pregnancy if you continue.
- The IUD can fall out.
- Neither type gives protection from STIs.
Differences between the copper and hormonal IUD
There are a number of differences between the copper and hormonal IUD.
Differences in menstruation include:
- After a hormonal IUD has been put in, you may have three to five months of frequent and irregular bleeding between periods. After this time, your periods may be shorter, lighter, and less painful. About 50 per cent of women stop bleeding all together.
- After a copper IUD has been put in, you may have a few weeks of irregular bleeding between periods. After this time, your periods may be heavier and more painful.
Differences in cost include:
- The hormonal IUD is covered by a health care card in Australia. It costs around $6 if you are a card holder and around $37 if you do not have a card.
- The copper IUD is not covered by a health care card and may cost around $120 outside a public hospital setting.
Differences in side effects include:
- The hormonal IUD may cause headaches, acne, breast tenderness and an increase in appetite in the first few months.
- The copper IUD has no hormonal side effects.
Differences in medical conditions include:
- The hormonal IUD should not be used if you have had breast cancer in the last five years.
- With rare exceptions, the copper IUD will not have any known effect on existing medical conditions.
Other types of contraception
There are many contraceptive methods available in Australia. When you are choosing the method that is right for you, it is important to have access to accurate information and to talk openly about your options with your partner.
It is also important to think about how well each method works, the possible side effects, how easy it is to use and how much it costs. It is important to weigh the pros against the cons, and think about how each method meets your current and future needs. The method you choose will depend on your general health, lifestyle and relationships. It can help to talk about your options with a doctor or reproductive health nurse.
Protection from sexually transmissible infections
IUDs, both copper and hormonal, do not give protection from sexually transmissible infections (STIs). It is important to practise safer sex, as well as to prevent an unintended pregnancy. The best way to lessen the risk of STIs is to use barrier methods, such as condoms for oral, vaginal and anal sex with all new sexual partners. Condoms can be used with IUDs to help stop infections from spreading.
Where to get help
Things to remember
- Intrauterine devices (IUDs) are small contraceptive devices that are put into the uterus (womb) to prevent pregnancy.
- The two types available are the copper IUD and the hormonal IUD (MirenaTM).
- Both types are very effective methods of contraception and can stay in place for five to eight years.
- IUDs, both copper and hormonal, do not give protection from sexually transmissible infections (STIs). The best way to lessen the risk of STIs is to use barrier methods such as condoms with all new sexual partners.
This page has been produced in consultation with and approved by:
Family Planning Victoria
Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your doctor or other registered health professional. Content has been prepared for Victorian residents and wider Australian audiences, and was accurate at the time of publication. Readers should note that, over time, currency and completeness of the information may change. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions.