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(intrauterine levonorgestrel delivery system)
Consumer Medicine Information
The information in this leaflet is only a summary and is not a complete statement about MIRENA. Your doctor has more detailed information relating to you, your medical history and this system and you should consult your doctor if you have any concerns about using MIRENA.
Please read this leaflet carefully and keep it, as you may need to read it again. Please contact your doctor if you have any questions about your treatment with MIRENA or if you have any difficulties whilst using MIRENA.
MIRENA consists of a small T-shaped frame made from a plastic called polyethylene. This carries 52 mg levonorgestrel, a hormone used in many contraceptive pills. The hormone is contained within a substance called dimethylsiloxane/methylvinylsiloxane (cross-linked) elastomer. This is surrounded by a membrane (skin) made of dimethylsiloxane/ methylvinylsiloxane (cross-linked) elastomer.
The T-shaped frame also contains barium sulphate so that it can be seen on X-rays.
This structure provides a system for releasing the hormone gradually into the uterus (womb).
There are two fine threads, made of iron oxide and polyethylene, attached to the bottom of the frame. These allow easy removal and allow you or your doctor to check that the system is in place.
MIRENA may be used as a long term and reversible method of contraception, for the treatment of excessive menstrual bleeding (Menorrhagia) or for protection from endometrial hyperplasia (excessive growth of the lining of the womb) during hormone replacement therapy. It is placed inside the womb where it slowly releases the hormone (at an initial rate of 20 micrograms per day) over a period of five years or until it is removed.
Not all women should use MIRENA. All products have benefits and risks. If you are unsure if MIRENA is suitable for you, discuss this with your doctor.
You should not use Mirena if:
MIRENA may be used with caution after specialist consultation or your doctor may consider removal of the system if any of the following conditions exist or arise for the first time:
In women using contraceptive pills containing progestogen only, some recent studies indicated that there may be a slightly increased risk in venous blood clots, but the results were not very certain. However you should see your doctor immediately if you have any symptoms or signs of clots. Such symptoms or signs can include:
Symptoms or signs indicating blood clots in the vessels of your eye are: unexplained partial or complete loss of vision, double vision or any other unexplained disturbances in your eyesight.
It is still under discussion whether varicose veins and superficial thrombophlebitis (inflammation of a vein with a clot formation) are associated with venous blood clotting.
In diabetic users, the blood glucose concentration should be monitored. However there is no need to alter the therapeutic regimen of Type 1 diabetics using Mirena.
Breast cancer has been detected slightly more often in women who use combined oral contraceptives (the pill) compared to women of the same age who do not use the pill. It is not known whether the difference is caused by the pill or whether cancers were detected earlier in pill users. The evidence is not conclusive for progestogen-only presentations such as Mirena Should breast cancer be diagnosed then removal of Mirena should be considered.
MIRENA should not be the first choice of contraception in young women who have not had a baby because of the possibility of more sexual partners and an increased risk of infections. Pelvic infection may impair fertility and increase the risk of ectopic pregnancy.
Your doctor will need to determine the position and the size of your womb.
The system should be inserted either during your period or within seven days from the beginning of your period. If you already have the system and it is time to replace it with a new one, you do not need to wait for your period.
Mirena can be inserted immediately after abortion as long as there are no genital infections. It should not be used until six weeks after delivery.
When MIRENA is used to protect the lining of the womb during oestrogen replacement therapy, it can be inserted at any time if you do not have monthly bleeding or else during the last days of menstruation or withdrawal bleeding.
You may feel faint after the system is fitted. This is normal and your doctor will tell you to rest for a while. In very rare cases during fitting, part or all of the system could penetrate the wall of the womb. If this happens the MIRENA needs to be removed.
The current recommendation is to wait about 24 hours after having the MIRENA inserted before having sexual intercourse.
Rarely, most often during insertion Mirena can perforate the wall of the womb. If this happens the IUS must be removed as soon as possible. If you experience excessive pain or bleeding tell your doctor.
There is a small amount of the progestogen hormone levonorgestrel, which will be absorbed by babies who are breastfeeding when the MIRENA is used. This is an equivalent amount to that received by babies when the mother is using a progestogen only contraceptive (the minipill). There has been extensive experience with the minipill during breastfeeding, indicating no harmful effects to breastfed babies.
However this is a serious condition that requires immediate medical attention.
The following symptoms could mean that you may have an ectopic pregnancy and you should see your doctor immediately:
All medicines carry some risk of side effects. With MIRENA these are most common during the first months after the system is fitted and decrease as time goes on. It is normal to experience changes in menstrual patterns during the use of MIRENA. The changes may include spotting, shorter or longer menstrual periods, irregular bleeding, prolonged periods of no bleeding at all, heavy flow and menstrual pain. Apart from menstrual changes, possible side effects might include:
If while using MIRENA, you experience any unwanted effects or symptoms which may be due to MIRENA (whether or not it is mentioned), please tell your doctor as soon as possible. You may need medical treatment if you experience any of the following unwanted effects:
MIRENA is a small, white coloured T-shaped plastic system with black threads attached to the vertical arm.
MIRENA is contained within an insertion device and is provided in a sterile pouch for insertion by a doctor experienced in the insertion of intrauterine systems.
MIRENA works in the treatment of excessive monthly bleeding and as protection in oestrogen replacement therapy by slowly releasing the progestogen hormone levonorgestrel, within the womb. Levonorgestrel suppresses the response of the cells in the lining of the womb to oestrogen making the lining of the womb insensitive to circulating oestradiol. This stops the growth of the lining of the womb, which results in a reduction in the volume and duration of menstrual bleeding. This is the mechanism of action in the treatment of excessive bleeding (menorrhagia) and for protection against over stimulation of the lining of the womb in oestrogen replacement therapy.
The hormone in MIRENA prevents pregnancy by:
BAYER AUSTRALIA LIMITED
ABN 22 000 138 714
875 Pacific Highway
PYMBLE NSW 2073
Australia
Bayer New Zealand Limited
3 Argus Place
Hillcrest, Northshore 0627
New Zealand
Date of preparation: September 2007
Published by MIMS/myDr December 2008