Implanon is a progestogen-only contraceptive implant. It consists of a small, flexible rod which is inserted just under the skin on the inside of your upper arm. A small amount of progestogen is released from the rod every day. This prevents pregnancy by inhibiting ovulation (the monthly release of an egg from your ovaries) It also thickens the cervical mucus, thereby preventing sperm from entering the womb.
It is suitable for most women looking for reliable, long term contraception. You should discuss your medical details with the nurse or doctor to check its suitability. It would not be recommended for any woman with hormone dependent cancers; any active thrombosis; severe liver disease; known or suspected pregnancy; undiagnosed, unusual vaginal bleeding; allergy to the components of the implant.
If fitted on the first day of your period, protection against pregnancy starts from the day of fitting for up to three years. If you are heavier than normal, it may need replacing earlier. If Implanon is fitted at any other time, you will need to use additional methods of contraception for 7 days.
Implanon is highly effective, certainly as effective as the combined contraceptive pill and the currently used progestogen injection.
Implanon is not affected by antibiotics, but may be affected by some other drugs, eg anti-epileptic, or anti-TB drugs. It is NOT affected by diarrhoea or vomiting.
The commonest side effects associated with Implanon are irregular periods, weight gain, acne, headache and breast tenderness. As with other hormonal methods of contraception, many of the effects will improve in time. Most women have regular periods after the first year, but around one-third of women still have irregular bleeding, which can be heavy and frequent, although this is less common. Some women lose their periods completely. It is wise to expect some change in your periods initially.
Rarer side effects include hair loss, mood changes, change in libido, abdominal pain and painful periods.
Insertion is very quick, taking a couple of minutes. You may be given some local anaesthetic to numb the skin. A pressure bandage will be put on your arm to reduce bruising. Keep the area dry and clean. After 24 hours, remove the bandage and use your arm normally. When the anaesthetic has worn off, your arm may be a little tender and bruised for a few days.
The rod is not usually visible, unless you are very thin. You will be able to feel it with your fingertips. Shortly after injection, a small layer of tissue forms around the rod, preventing its movement and keeping it in place.
Implanon must be removed after three years. You will be given a card reminding you of the date by which the implant must be removed. Removal takes about 3 minutes. Local anaesthetic is used to numb the area. A small cut is made at one end of the rod, which is then removed. After removal a pressure bandage will be put on to reduce bruising. There is a slight possibility of a small scar from the incision.
If you have changed doctors, ask whether your new doctors is trained in the removal procedure; if not, ask for referral to another clinic for the removal.
Within a few days after removal of the rod, the hormone will be out of your system. Your normal level of fertility will return and most women ovulate within 3 months of removal. it is recommended that you consider your contraceptive needs as soon as the rod has been removed, if not before.
Implanon can be injected between day 21 and 28 after having a baby, unless you are breastfeeding. It is currently not recommended for breastfeeding mothers.
You will be asked to attend for a follow-up appointment 3 months after insertion. At this time, your blood pressure will be checked and you will be asked about any side effects.
Family Planning Association
Margaret Pyke Centre
This article published on
01 August 2005
Next review date 8/1/2013
Contraception and pregnancy
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