The intra-uterine device, or IUD, is a form of contraception for women, to prevent pregnancy. An IUD is also commonly called an intrauterine contraceptive device (IUCD), 'The coil’ or ‘Loops’.
- An IUD is a small, T-shaped plastic device that is inserted into your uterus (womb) and has a thread tied to the end which hangs down through the cervix into the vagina.
- It's a long-acting form of contraception, which means that once it's inserted you don't have to remember about it every day or every time you have sex.
- Its effect is reversible which means that your natural fertility returns when the IUD is removed.
Types of IUD
In Aotearoa New Zealand there are two types of IUD:
- hormonal IUDs containing progestogen (Mirena®, Jaydess®)
- copper IUDs.
Hormone or progestogen IUD
This is also called an intrauterine system (IUS). The hormonal IUD contains a progestogen called levonorgestrel that it releases slowly into the womb.
Progestogen prevents pregnancy by making the mucus in your cervix thicker so sperm can’t travel through it to get to your egg. It also affects the lining of the uterus, making it unsuitable for a fertilised egg to implant and grow.
Progestogen hormones in this IUD also reduce menstrual bleeding and cramping. Because of this, it’s often used to treat menorrhagia (heavy periods).
Examples of the hormonal or progestogen-only IUD are Mirena® and Jaydess®.
Mirena® is effective for 5 years, while Jaydess® is effective for 3 years. At the end of this time, your IUD will need to be replaced with a new one.
Copper IUD
The copper IUD works by releasing tiny amounts of copper into the womb which damages or kills the sperm, and also affects the lining of the uterus, making it unsuitable for a fertilised egg to implant and grow.
- The copper IUD is generally effective for 5 years and is usually changed 5 years after insertion.
- Your healthcare provider will advise you if your IUD can be left for longer.
- The copper IUD can be used as emergency contraception. Read more about emergency contraception.