Contraceptive implants
Implanon NXT® is a long-acting reversible contraceptive (LARC) that slowly releases the hormone progestogen. It is inserted under the skin of the inner upper arm and is effective for up to 3 years. Progestogen works by:
- Stopping the release of an egg by the ovary (ovulation)
- Making the mucus (sticky fluid) at the opening of the uterus thicker so sperm can't get through.
It is a small plastic rod, about the size of a matchstick, which contains a progesterone hormone.
The implant is inserted by a doctor or health service. A local anaesthetic is given to make the area numb before the implant is inserted.
Things to consider
- It is a ‘fit and forget’ method meaning. Once it is in place, it lasts up to 3 years.
- It is effective as soon as it is in place.
- It does not contain oestrogen and may be safer for some people, including smokers.
- Body weight, stomach upsets or medications do not reduce its effectiveness.
- It can be removed, with fertility returning after a month for most people.
- Many people have very light periods or may completely stop having periods.
- It is not suitable for people who may be pregnant, have liver disease or extremely heavy menstrual bleeding.
- It may cause side effects such as irregular bleeding painful periods, nausea or mood swings. If this happens, see your doctor.
- The initial cost is high, but it is not expensive when averaged over 3 years.
- Implanon can be used while breastfeeding (but check with your doctor first).
- Does not protect against STIs.
Last reviewed: 29-10-2025
Acknowledgements
Sexual Health and Blood-borne Virus Program, Public Health
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