Contraception - intrauterine devices

An intrauterine device (IUD) is a small contraceptive device that is inserted into the uterus to prevent pregnancy. There are two types of intrauterine device: the copper IUD and the progestogen or hormonal (Mirena) IUD. Progestogen is a synthetic version of the natural progesterone produced by the ovaries. Both types of IUD provide a very effective form of contraception, which can stay in place and protect against pregnancy for at least five years.

IUDs work by affecting the way sperm move and survive in the uterus (womb), so sperm cannot reach the egg to fertilise it. They can also cause changes to the lining of the womb (endometrium) so an egg cannot develop, even if it is fertilised.

In addition to these effects, the hormonal or progestogen IUD may thicken the mucus made by the cervix (neck of the womb). This blocks sperm from entering the uterus. It may also cause some changes to hormones responsible for ovulation (releasing of an egg).

The copper IUD
The copper IUD is a small plastic device with copper wire wrapped around its stem. It has a fine nylon string attached to it. When the IUD is in place, the string comes out through the cervix (the neck of the womb) into the top of the vagina. This piece of string lets you check that the IUD is still in place and makes it easy for a doctor to remove the device. You can’t feel the string unless you put your finger deep inside your vagina.

The progestogen IUD
The progestogen IUD is a small plastic T-shaped device with a cylinder around its stem. The cylinder contains progestogen, a synthetic progesterone-like hormone. The cylinder is covered with a membrane that regulates the release of the progestogen into the uterus (womb). The device available in Australia is called Mirena. Like the copper IUD, it has a fine nylon string attached to make checking and removing easier.

Advantages of IUDs:

• Very effective – more than 99 per cent effective in preventing pregnancy
• Last between five and eight years
• Can be removed at any time with a quick return to fertility
• Can be ‘forgotten’ about, once inserted (except to check the strings).

• Must be inserted by a doctor trained in the technique – there may be associated costs and access issues
• Small risk of infection at time of insertion
• May be an increase in the risk of pelvic inflammatory disease (infection of the pelvic organs including the fallopian tubes) in women exposed to sexually transmissible infections (STIs)
• A small risk of perforation (the IUD going through the wall of the uterus when it is inserted)
• Possible complications with unintended pregnancies
• No protection against sexually transmissible infections (STIs)
• Can fall out.

• Hormonal – after a hormonal IUD is inserted, women may have three to five months of frequent irregular spot bleeding. After this, women generally get short, light, painless periods. About 20 per cent of women stop bleeding completely.
• Copper­ – after a copper IUD is inserted, there may be a few weeks of irregular spot bleeding. After that, periods may be heavier and sometimes more painful.
• Cost
• Hormonal – a hormonal IUD is covered by a health care card. It costs $5 for card holders and $31.30 for those who do not have a card.
• Copper – A copper IUD is not covered by a health care card and may cost around $100 outside a public hospital setting.

• Hormonal – a hormonal IUD may cause headaches, acne, breast tenderness and an increase in appetite. These symptoms seldom persist beyond the first few months of use.
• Copper – a copper IUD has no hormonal side effects.

• Hormonal – hormonal IUDs should not be used by women who have had breast cancer in the last five years.
• Copper – a copper IUD does not have any known impact on existing medical conditions.

• Your doctor
• Family Planning Victoria Tel. 1800 013 952 or (03) 9257 0100 www.fpv.org.au
• Family Planning Victoria’s Action Centre (for young people under 25) Tel. (03) 9654 4766 or 1800 013 952
• RWH Women’s Health Information Centre Tel. (03) 9344 2007
• Melbourne Sexual Health Centre Tel. (03) 9341 6200 or 1800 032 017 or TTY (for the hearing impaired) (03) 9347 8619
• Community health centre
• Reproductive specialist
• Pharmacist

• Intrauterine devices (IUDs) are small contraceptive devices that are inserted into the uterus.
• There are two types available: the copper IUD and the progesterone (Mirena) IUD.
• IUDs provide a very effective form of contraception, which can stay in place and protect against pregnancy for five to eight years.
• Condoms provide the best available protection against sexually transmissible infections (STIs).

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