Implanon is small, thin, plastic rod, about the size of a matchstick (40 mm long and 2 mm wide), containing progesterone hormone. It is inserted underneath the woman's skin, usually on the inside of her upper arm, using local anaesthetic. Implanon works in a similar way to progesterone injections, by stopping ovulation, thinning the lining of the uterus and thickening the mucous in the cervix. It lasts for three years, unless removed before this time and is more than 99% effective. About 0.1% of implants are inserted incorrectly, making them ineffective.
Image 12-78 shows an Implanon implant.
Side effects. Possibly irregular, light spotting, or frequent bleeding. A few women experience acne, headaches, weight gain, breast tenderness, dizziness, depression and/or loss of libido. There may be some bruising around the insertion site for a week or so afterwards.
Breastfeeding. At this stage, Implanon is not officially licensed for use during breastfeeding in Australia, but it is thought not to have effects on the baby, similar to progesterone injections.
Advantages of Implanon are:
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Set and forget. No pills or repeated injections. |
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After removal, fertility usually returns to normal within three to four weeks. |
Disadvantages of Implanon are:
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It needs to be inserted and removed by a doctor trained to do this. (Many GP's can insert them.) |
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The effectiveness may wear off after two years for women who are overweight for their height. |
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If you don't like the side effects, it will need to be removed early. |