Intrauterine Contraceptive Device (IUD)
An intrauterine device (IUD) is a type of contraception (birth control). IUDs are small devices that go inside your uterus to stop you becoming pregnant. IUDs are also called long-acting reversible contraceptives (LARCs).
Types of IUD
There are 2 types of IUD — the hormonal IUD and the copper IUD.
The Hormonal IUD
Hormonal IUDs are made of plastic and slowly release a progestogen hormone called levonorgestrel. There are 2 brands of hormonal IUDs in Australia: Mirena and Kyleena. Kyleena has a lower dose of hormone than Mirena. Hormonal IUDs work for up to 5 years.
The hormonal IUD stops pregnancy by:
- thickening the mucus at the entrance to the uterus so sperm can't get through
- making it harder for sperm to reach and fertilise an egg
- making it harder for an egg to survive
- thinning the lining of the uterus
- stopping ovulation (the release of eggs from the ovaries) in some people
After having a hormonal IUD put in, you may need to use another form of contraception for 7 days. Check with your doctor or nurse about this.
The Copper IUD
The copper IUD is made of copper and plastic. It doesn't release any hormones. There are 2 brands of copper IUD on the market in Australia. They last for up to 10 years.
The copper IUD works by:
- making it harder for sperm to reach and fertilise an egg
- making it harder for an egg to survive
- changing the lining of the uterus so that if an egg is fertilised, it can't implant
Additionally, the copper IUD can be used as a type of emergency contraception. It must be put in within 5 days of unprotected sex.
Comparison of IUD Types
| Feature | Hormonal IUD | Copper IUD |
|---|---|---|
| Materials | Plastic and progestogen | Copper and plastic |
| Duration | Up to 5 years | Up to 10 years |
| Hormones | Levonorgestrel | None |
| Emergency Use | No | Yes (within 5 days) |
How Effective is the IUD?
The IUD is a very effective method of contraception. Less than 1 in 100 people using an IUD will become pregnant.
Insertion and Aftercare
IUDs can only be put in by a specially trained doctor or nurse. Getting an IUD put in, is a bit like having a cervical screening test. You lie on your back, and an instrument called a speculum is put in your vagina. Local anaesthetic can reduce your discomfort or pain.
For a couple of days after getting an IUD, you should avoid:
- using tampons or menstrual cups
- having sex
- having a bath
- swimming
You should check the IUD thread about once a month to make sure your IUD is still in place. You will be shown how to do this.