This health information is general information only.If you have any concerns about your sexual health, please see a doctor or visit one of our clinics.
What Is It?
Implanon is a contraceptive rod containing the hormone etonogestrel, which is similar to the naturally occurring hormone, progesterone, made by a woman’s ovaries.
It is about the size of a match – four centimetres long and two millimetres wide.
It is inserted under the skin of the inner upper arm. Once inserted, it can be felt, but not easily seen.
How Effective Is It?
Implanon is the most effective reversible method of contraception available. It is more than 99.9% effective.
How Does It Work?
It stops the body from releasing an ovum (egg) each month.
It thickens the mucus in the cervix (the entrance to the womb), preventing sperm from getting through.
How Do I Use Implanon?
Implanon must be inserted by a doctor who has been trained in this technique.
Insertion takes a few minutes, with local anaesthetic used to prevent discomfort.
After the anaesthetic wears off (within a few hours), there is usually some soreness and bruising, which settles within a few days.
Implanon can be left in for up to three years before it needs to be removed or replaced.
The doctor will inject local anaesthetic under the implant, make a small cut in the skin and remove the Implanon rod.
This usually takes 10–15 minutes and should be straightforward for a doctor trained in Implanon procedures.
You will have a small scar, but won’t have any stitches. You can have a new rod inserted at the same site.
On very rare occasions, the rod is deeper than usual and may need to be removed with ultrasound guidance. This will be done in a hospital by a specialist. The doctor will discuss this with you if necessary.
When does it start working?
If Implanon is inserted during the first five days of a normal period, the contraceptive effect starts immediately.
It can be inserted at other times in your menstrual cycle if pregnancy is ruled out. In this case, it takes seven days to become effective.
What stops Implanon from working?
St John’s Wort (a natural remedy) and some medications (mostly those used to treat epilepsy) may interfere with Implanon.
If you are taking any of these remedies or medications, you should discuss this with your doctor or family planning clinic.
What are the advantages?
Implanon is highly effective, inexpensive and usually easily reversible.
You don’t have to remember to take a pill every day, as the hormone is released slowly and continuously into the bloodstream.
Bleeding may be lighter and less painful or your periods may stop.
When Implanon is removed, the contraceptive effect and any side effects are quickly reversed.
It can usually be used if you are unable to use contraception containing oestrogen.
Your contraception will not be affected if you have diarrhoea or vomiting.
Implanon is safe to use if you are breastfeeding.
What are the disadvantages?
Implanon can only be inserted and removed by a specially trained doctor. You may have to pay for the procedure and service may be difficult to obtain in some areas.
You may experience pain and bruising in the area where Implanon is inserted.
Your bleeding pattern will change and may be unpredictable.
Implanon will not protect you against sexually transmissible infections (STIs). Use condoms to protect yourself against STIs, especially with all new sexual partners.
Occasionally, women need to be referred to a specialist for removal.
Who shouldn’t use Implanon?
Women who have had breast cancer within the last five years and women taking certain medications should not use Implanon.
Women who have had blood clots, heart disease, stroke, liver disease or certain types of migraine will need to consult their doctor, but can usually use Implanon safely.
What are the side effects?
All women given Implanon will experience a change in their bleeding pattern.
Some will stop having periods completely. This is not harmful, but some women do not like this experience.
Some may have irregular bleeding, which may be frequent and unpredictable. This often settles in the first three to four months of use.
Some women will have persistent bleeding or spotting.
Other possible side effects are acne, breast tenderness, a lower sex drive, increased appetite and headaches.
Is it for me?
Implanon may be right for you if you:
want a method that’s ‘fit and forget’
want the most effective method available (besides sterilisation)
find it hard to remember to take a tablet every day
don’t mind some irregular bleeding
have painful periods
would like a contraceptive that may improve acne.
What if I become pregnant?
There is no evidence that Implanon can harm a pregnancy.
You may safely choose to continue with the pregnancy or have an abortion.
Other things you should know
What if I don’t like Implanon or want to become pregnant?
Implanon can be removed at any time. Unless side effects are severe, you should try to keep Implanon in for at least three months, as there’s a good chance any side effects will settle in this time.
After removal, any side effects should be reversed within weeks and you should start to ovulate (release eggs) again. When you stop using Implanon, you have the same chance of becoming pregnant as you had before you started.
Can I use Implanon while I’m breastfeeding?
Yes. Implanon is safe to use no matter what age your baby is.
Will I gain weight while using Implanon?
While some women report weight gain, most women will not experience a significant change in weight while using Implanon.
What happens if I have Implanon in for more than three years?
If you are unable to have your Implanon changed before its three years of use have passed, it is extremely important you use an additional method of contraception, such as condoms, until seven days after you have had your Implanon replaced.
- You should follow the detailed instructions provided with your Implanon packet and by your doctor or nurse.
- You should discuss any further questions with your doctor or call your local family planning clinic.
- If needed, emergency contraception is available from pharmacies without a doctor’s prescription. See the FPV Emergency Contraception pamphlet for more information.