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MIRENA INTRA-UTERINE SYSTEM
Active substance(s): LEVONORGESTREL
Patient Information Leaflet
This product is known by the above name, but will be referred to as
Mirena throughout the remainder of the leaflet
About this leaflet
Please read this leaflet carefully before you decide to have Mirena
It provides you with some useful information about Mirena. The
information in this leaflet applies only to Mirena. If you have any
questions or are not sure about anything, please ask your doctor or
In this leaflet:
1. What Mirena is and what it is used for
2. Before you have Mirena fitted
3. How and when Mirena is used
4. Possible side effects
5. How to store Mirena
6. Further information
1. What Mirena is and what it is used for
Mirena is an intrauterine system (IUS) placed inside the womb
(uterus) where it slowly releases the hormone levonorgestrel. It can
be used in the following three ways:
1. As an effective long-term and reversible method of
2. For reducing menstrual blood flow, if you suffer from heavy
periods (heavy menstrual bleeding).
It can be used for contraception and heavy menstrual bleeding until
it is removed or up to a maximum of 5 years.
3. If you are going through the menopause Mirena can be used in
conjunction with an oestrogen as part of a hormone replacement
therapy (HRT) regimen to protect the lining of your womb.
Not so much is known about how well Mirena protects the lining of
the womb beyond 4 years of use in women who are taking
oestrogen to treat menopausal symptoms. Therefore, if you are
using it in this way, your doctor or nurse will remove your Mirena
after 4 years. Your doctor will be able to advise you further.
Children and adolescents
Mirena is not indicated for use before the first menstrual bleeding
How does Mirena work?
As a contraceptive:
The hormone in Mirena prevents pregnancy by:
controlling the monthly development of the womb lining so that
it is not thick enough for you to become pregnant
making the mucus in the opening to the womb (the cervical
canal) thicker, so that the sperm cannot get through to fertilise
preventing the release of eggs (ovulation) in some women.
There are also some effects on the lining of the womb caused by
the presence of the T-shaped frame of the Mirena device.
In the treatment of heavy menstrual bleeding:
The hormone in Mirena reduces menstrual bleeding by controlling
the monthly development of the womb lining, making it thinner, so
that there is less bleeding every month.
As part of an HRT regimen:
The menopause is a gradual process which usually takes place
between the ages of about 45 and 55. Although the menopause is
natural, it often causes distressing symptoms such as hot flushes
and night sweats. These symptoms are due to the gradual loss of
the female sex hormones (oestrogen and progestogen) produced
by the ovaries.
Oestrogens can be used to relieve the menopausal symptoms.
However, taking oestrogens alone increases the risk of abnormal
growth or cancer of the lining of the womb. Taking a progestogen,
such as the hormone in Mirena (levonorgestrel), as part of an HRT
regimen lowers this risk by protecting the lining of the womb.
2. Before you have Mirena fitted
Your doctor or nurse will carry out some tests before you have
Mirena fitted to make sure that it is suitable for you to use. This will
include a pelvic examination so that pregnancy and sexually
transmitted diseases can be excluded and may also include other
examinations such as a breast examination, if your doctor or nurse
feels this is appropriate.
Genital infections will need to be successfully treated before you
can have Mirena fitted.
If Mirena is to be fitted for HRT use your doctor will firstly carry out
an assessment of your symptoms to ensure that treatment is only
initiated for symptoms that adversely affect your quality of life. Such
an assessment should be repeated by your doctor at least
annually. You should also consult the Patient Information Leaflet of
the oestrogen product that is to be used in conjunction with Mirena
before starting your HRT regimen as there are some important risk
factors associated with HRT that you should consider, such as the
risk of endometrial cancer, breast cancer and blood clots. You may
feel pain or have some bleeding during insertion.
If you have epilepsy, tell the doctor or nurse fitting the Mirena
because, although rare, a fit can occur during insertion. Some
women might feel faint after the procedure. This is normal and your
doctor or nurse will tell you to rest for a while.
Do not use Mirena and please tell your doctor or nurse if you:
are pregnant or suspect that you may be pregnant
have or have had any type of cancer or suspected cancer
including blood cancer (leukaemia) unless in remission,
uterine, cervical and breast cancer
currently have or have had recurrent pelvic inflammatory
have or have had inflammation of the neck of the womb
have an unusual or unpleasant vaginal discharge, or vaginal
itching as this may indicate an infection
have or have had inflammation of the lining of your womb
following delivery of your baby
have or have had an infection of the womb after delivery or
after abortion during the past 3 months
have any condition which makes you susceptible to infections.
A doctor will have told you if you have this
have or have had an abnormal smear test (changes in the
have undiagnosed vaginal bleeding
have an abnormal womb or abnormal growths in the womb
(fibroids) which distort the uterine cavity
have or have had liver problems
have or have had trophoblastic disease. A doctor will have told
you if you have this
are sensitive to the hormone levonorgestrel or to any of the
ingredients in Mirena (see section 5 ‘What Mirena contains’).
Mirena must not be used as part of an HRT regimen if you have
had a stroke, heart attack or any heart problems.
Mirena may not be suitable for all women.
Consult your doctor or nurse if you:
have or develop migraine with visual disturbances, unusually
bad headaches or if you have headaches more often than
have yellowing of the skin or whites of the eyes (jaundice)
have high blood pressure
have had a cancer affecting your blood (including leukaemia)
which is now in remission
are on long-term steroid therapy
have ever had a previous ectopic pregnancy (pregnancy
outside the womb)
have a history of fluid filled sacks in the ovary (ovarian cysts)
are having Mirena fitted for contraception or heavy menstrual
bleeding and have had a stroke or heart attack, or if you have
any heart problems
disease of your arteries (arterial disease)
have a history of blood clots (thrombosis)
are diabetic, as Mirena may affect glucose tolerance.
You may still be able to use Mirena if you have or have had some
of these conditions.
Your doctor or nurse will advise you.
You must also tell your doctor or nurse if any of these conditions
occur for the first time while you have Mirena in place.
You must see a doctor or nurse as soon as possible if you
develop painful swelling in your leg, sudden chest pain or
difficulty breathing as these may be a sign of a blood clot. It is
important that any blood clots are treated promptly.
contraceptive method. Please ask your doctor or nurse for advice
3. How and when Mirena is used
Only a doctor or specially trained nurse can fit Mirena. They will
explain the fitting procedure and any risks associated with its
usage. You will then be examined by your doctor or nurse before
Mirena is fitted. If you have any concerns over its usage you should
discuss it with them.
When Mirena is fitted for contraception or heavy menstrual
Mirena should be inserted either during your period or within seven
days from the beginning of your period. If you already have Mirena
and it is time to replace it with a new one, you do not need to wait
until your period. If you have just had a baby, you should wait at
least 6 weeks before having Mirena fitted (see section 4 ‘Possible
side effects – Severe pain and continued bleeding’). Mirena can
sometimes be fitted immediately after you have had an abortion,
provided that you have no genital infections.
You must also see a doctor without delay if you develop
persistent lower abdominal pain, fever, pain during sexual
intercourse or abnormal bleeding. If you get severe pain or fever
shortly after Mirena has been inserted, you may have a severe
infection which must be treated immediately.
When Mirena is fitted for HRT use:
If you no longer have periods then Mirena can be inserted at any
time. If you still have periods, Mirena should be inserted during the
last days of bleeding.
It is advisable to give up smoking when using hormone containing
products such as Mirena.
Remind your healthcare provider that you have Mirena inserted,
especially if they were not the person who inserted it.
Can I change my mind?
Your doctor or nurse can remove Mirena at any time. Unless you
wish to get pregnant the removal should be carried out during the
first few days of your period. Otherwise it is important to use
another form of contraception (e.g. condoms) in the 7 days leading
up to the removal as intercourse during this week could lead to
pregnancy after Mirena is removed.
How quickly does Mirena work?
You are protected from pregnancy as soon as Mirena is fitted. The
possibility of becoming pregnant is approximately 2 in 1,000 in the
first year. The failure rate may increase in case of the Mirena
coming out by itself or perforation (see section 4 ‘Possible side
If you do wish Mirena to be removed so that you can get pregnant
your usual level of fertility is expected to return after it is removed.
Studies have suggested that in women who discontinue Mirena (in
order to become pregnant) the pregnancy rate at one year is similar
to those who do not use contraception.
Heavy menstrual bleeding:
Mirena usually results in lighter periods after 3 to 6 months of
Taking other medicines
The effect of hormonal contraceptives such as Mirena may be
reduced by medicines that increase the amounts of enzymes made
by the liver. Please tell your doctor or nurse if you are taking:
phenobarbital, primidone, phenytoin or carbamazepine (to treat
griseofulvin (an antifungal)
rifampicin or rifabutin (antibiotics)
nevirapine or efavirenz (for HIV).
Please tell your doctor or nurse if you are taking or have recently
taken any other medicines, including medicines obtained without
Pregnancy and breastfeeding
Mirena should not be used during pregnancy or if you think
you are pregnant.
It is very rare for women to become pregnant with Mirena in place.
Missing a period may not mean that you are pregnant as some
women may not have periods at all while using Mirena. However, in
order to exclude the possibility of pregnancy, you should consider a
pregnancy test if you have not had a period for 6 weeks. If this test
is negative there is no need to carry out another test, unless you
have other signs of pregnancy, e.g. sickness, tiredness or breast
If you do become pregnant with Mirena in place, please contact
your doctor as soon as possible so that ectopic pregnancy can be
excluded and Mirena removed to reduce the risk of spontaneous
Very small amounts of the hormone in Mirena are found in breast
milk but the levels are lower than with any other hormonal
The hormone in Mirena will begin to protect the lining of your womb
as soon as it is fitted.
How often should I have Mirena checked?
You should have it checked 6 weeks after it is fitted. Your doctor
may determine how often and what kind of check-ups are required
in your particular case.
How can I tell whether Mirena is in place?
Gently put a finger into your vagina and feel for the two thin threads
attached to the lower end of Mirena. Your doctor or nurse will show
you how to do this.
Do not pull the threads because you may accidentally pull it out. If
you cannot feel the threads, contact your doctor or nurse as soon
as possible and in the meantime avoid intercourse or use a barrier
contraceptive (such as condoms). The threads may have simply
drawn up into the womb or cervical canal. If the threads still cannot
be found by your doctor or nurse, they may have broken off, or
Mirena may have come out by itself, or in rare cases it may have
perforated the wall of your womb (uterine perforation, see section
4). It may be necessary for you to have an ultrasound scan or x-ray
to locate Mirena.
Contact your doctor or nurse if you can feel the lower end of Mirena
itself or you or your partner feel pain or discomfort during sexual
What happens if Mirena comes out by itself?
If it comes out either completely or partially you may not be
protected against pregnancy.
It is rare but possible for this to happen without you noticing during
your menstrual period. An unusual increase in the amount of
bleeding during your period might be a sign that this has happened.
Tell your doctor or nurse if there are any unexpected changes in
your bleeding pattern.
How will Mirena affect my periods?
Mirena will affect your menstrual cycle.
For all uses of Mirena:
You may have lighter periods or painful periods or some spotting
(light bleeding in between periods) and irregular bleeding during the
first few months after Mirena is fitted.
You may have prolonged or heavy bleeding or an increase in the
frequency of bleeding, usually in the first 2 to 3 months, before a
reduction in blood loss is achieved.
Overall you are likely to have fewer days bleeding in each month
and you might eventually have no periods at all. This is due to the
effect of the hormone (levonorgestrel) on the lining of the womb.
If you have had Mirena fitted for heavy menstrual bleeding:
You should have lighter periods after 3 to 6 months. If you do not
have lighter periods after 3 to 6 months, alternative treatments
should be considered.
If you have had Mirena fitted for HRT use:
If you have had Mirena fitted for quite a long time and then start to
have bleeding problems, it is important that you contact your
doctor so that tests can be carried out to exclude changes to your
There is a calendar on the last page of this patient information
leaflet. Your doctor or nurse may ask you to fill this in to check your
pattern of bleeding. If you are asked to do so, mark the date of
insertion with an “X” in the appropriate date square. Mark days of
spotting with “o” and bleeding with “•”.
4. Possible side effects
Taking any medicine carries some risk of side effects. With Mirena
these are most common during the first months after it is fitted and
decrease as time goes on.
If you experience any of the following serious side effects
please contact your doctor or nurse immediately:
Severe pain or fever developing shortly after insertion may
mean that you have a severe infection which must be treated
immediately. In rare cases very severe infection (sepsis) can
Severe pain and continued bleeding as this might be a sign
of damage or tear in the wall of the womb (perforation).
Perforation is rare, but occurs most often during the fitting of
the Mirena, although the perforation may not be detected until
sometime later. If this happens the Mirena will be removed;
very rarely this may require surgery. The risk of perforation is
low, but increased in breastfeeding women and in women who
have had a baby up to 36 weeks before insertion.
Possible signs and symptoms of perforation may include:
severe pain (like menstrual cramps) or more pain than
heavy bleeding (after insertion)
pain or bleeding which continues for more than a few
sudden changes in your periods
pain during sex
you can no longer feel the Mirena threads (see section 3
‘How and when Mirena is used – How can I tell whether
Mirena is in place?’)
Lower abdominal pain especially if you also have a fever
or have missed a period or have unexpected bleeding, as
this might be a sign of ectopic pregnancy. The absolute risk of
ectopic pregnancy in Mirena users is low. However, when a
woman becomes pregnant with Mirena in place, the relative
likelihood of ectopic pregnancy is increased.
Lower abdominal pain or experience painful or difficult
sex as this might be a sign of ovarian cysts or pelvic
inflammatory disease. This is important as pelvic infections can
reduce your chances of having a baby and can increase the
risk of ectopic pregnancy.
Very Common (more than 1 in 10 women)
vaginal bleeding including spotting
absent, light or infrequent menstrual periods
Common (less than 1 in 10 women)
abdominal, pelvic or back pain
increased growth of hair on the face and body
reduced sex drive
increased vaginal discharge
inflammation of the vulva and vagina
tender, painful breasts
Mirena coming out by itself
Uncommon (less than 1 in 100 women)
genital infections that may cause: vaginal itching; pain on
passing urine; or lower abdominal pain from inflammation of
the womb, ovaries or Fallopian tubes
infection or inflammation of the lining of the womb, which may
cause a foul smelling vaginal discharge (endometritis)
inflammation of the neck of the womb (cervicitis)
swelling of your abdomen, legs or ankles
itchy skin including eczema
skin discolouration/increased skin pigment especially on the
Rare (less than 1 in 1000 women)
uterine perforation (see ‘serious side effects’ above)
allergic reaction (symptoms may include rash, itching or rapid
swelling of the face, mouth, tongue and/or throat)
increased blood pressure
Your partner may feel the removal threads during intercourse.
Every woman is at risk of breast cancer, but it is rare in women
under the age of 40. Breast cancer has been reported in Mirena
users, although the risk and frequency are unknown.
In pre-menopausal women, the frequency of developing breast
cancer whilst using Mirena is possibly similar to that associated
with using Combined Oral Contraceptives, but the evidence for this
is less conclusive.
In post-menopausal women, using hormone replacement therapy
(HRT) slightly increases the risk of breast cancer. Although the risk
of developing breast cancer is higher with combined
oestrogen/progestogen HRT, than with oestrogen-only HRT, the
risk of breast cancer developing when Mirena is prescribed to
provide the progestogen component of HRT is not yet known. The
patient information leaflet of the oestrogen component of the
treatment should also be consulted for additional information.
It is important to regularly check your breasts and you should
contact your doctor if you feel any lump in your breasts. You should
also tell your doctor if a close relative has or ever had breast
Date of insertion = X Spotting = Bleeding =
If any of the side effects gets serious, or if you notice any side
effects not listed in this leaflet, please tell your doctor or
Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse.
This includes any possible side effects not listed in this leaflet. You
can also report side effects directly via the Yellow Card Scheme at:
By reporting side effects, you can help provide more information on
the safety of this medicine.
5. How to store Mirena
Keep out of the sight and reach of children.
Do not use intra-uterine device after expiry date stated on the box.
No special storage conditions.
Medicines should not be disposed of via wastewater or household
waste. Ask your pharmacist how to dispose of medicines that are
no longer required. This will help to protect the environment.
6. Further Information
Mirena contains 52 milligrams of levonorgestrel. The hormone is
contained within a substance called polydimethylsiloxane.
This is surrounded by a membrane (skin) also made of
polydimethylsiloxane. The Mirena T-shaped frame also contains
barium sulphate so that it can be seen on X-rays.
What Mirena looks like and contents of the pack
Mirena consists of a small T-shaped frame made from a plastic
called polyethylene. 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 or nurse to check that
Mirena is in place.
Each sterile pack contains one Mirena and should not be opened
Manufactured by: BAYER OY, PANSIONTIE 47, 20210 TURKU,
FINLAND. Procured from within the EU. Product Licence Holder:
Quadrant Pharmaceuticals Ltd, Lynstock House, Lynstock Way,
Lostock, Bolton BL6 4SA. Repackaged by Maxearn Ltd, Bolton
Mirena Intra-Uterine System
Date of Fitting:……………………………………………………
Mirena is a registered trademark of Bayer Oy
Date of preparation 30 August 2016
First check-up visit:…………………………………………….
Mirena Intra-Uterine System
Medical Information Leaflet
Contraception. Idiopathic menorrhagia. Mirena may be particularly useful in
women with idiopathic menorrhagia requiring (reversible) contraception.
Protection from endometrial hyperplasia during oestrogen replacement
Posology and method of administration
Contraception and idiopathic menorrhagia
In women of fertile age, Mirena is inserted into the uterine cavity within
seven days of the onset of menstruation. It can be replaced by a new
system at any time of the cycle.
Post-partum insertion: To reduce the risk of perforation, postpartum
insertions should be postponed until the uterus is fully involuted. Do not
insert earlier than six weeks after delivery. If the patient is experiencing
significant post-partum bleeding and/or pain then infection or other causes
should be excluded before insertion. Mirena can also be inserted
immediately after the first trimester abortion.
Mirena is effective for 5 years in the indications for contraception and
idiopathic menorrhagia so should be removed after 5 years use. If the user
wishes to continue using the same method, a new system can be inserted
at the same time, in which case no additional protection is required.
If pregnancy is not desired, the removal should be carried out during the
first few days after the onset of the woman’s menstruation. Otherwise
contraception has to be ensured with other methods (e.g. condoms) starting
at least 7 days before the removal.
Protection from endometrial hyperplasia during oestrogen replacement
When used for endometrial protection during oestrogen replacement
therapy, Mirena can be inserted at any time in an amenorrhoeic woman, or
during the last days of menstruation or withdrawal bleeding.
In the indication for protection from endometrial hyperplasia during
oestrogen replacement therapy, clinical data (from clinical trials conducted
in women of 18 years and over) beyond 4 years of use are limited. Mirena
should therefore be removed after 4 years.
Mirena provides the progestogen component of hormone therapy (HRT).
Therefore in women receiving HRT, Mirena can be used in combination with
oral or transdermal oestrogen preparations without additional exogenous
progestogens. The product information of the oestrogen component of the
HRT should be consulted prior to the use of Mirena as the important risk
factors associated with HRT use should be considered, such as the risk of
endometrial cancer, breast cancer and venous thromboembolisms.
Instructions for use and handling
Mirena is supplied in a sterile pack which should not be opened until
required for insertion. The exposed product should be handled with aseptic
precautions. If the seal of the sterile package is broken, the product should
be discarded (see ‘Special precautions for disposal’).
How to Insert Mirena
It is strongly recommended that Mirena should only be inserted by
physicians/healthcare professionals who are experienced in Mirena
insertions and/or have undergone sufficient training for Mirena insertion.
In case of difficult insertion and/or exceptional pain or bleeding during or
after insertion, please refer to ‘Special warnings and precautions for use:
Insertion/removal warnings and precautions.’ Please see the ‘Insertion
instructions’ section on a separate leaflet.
How to Remove Mirena
Please see the ‘Insertion instructions’ section on a separate leaflet.
There are no relevant indications for use of Mirena before menarche.
Mirena has not been studied in women over the age of 65 years.
Patients with hepatic impairment
Mirena is contraindicated in women with acute liver disease or liver tumour
Patients with renal impairment
Mirena has not been studied in women with renal impairment.
Known or suspected pregnancy; confirmed or suspected hormone
dependent tumours including breast cancer; current or recurrent pelvic
inflammatory disease; cervicitis; current genital infection; postpartum
endometritis, infected abortion during the past three months; conditions
associated with increased susceptibility to infections; cervical dysplasia;
uterine or cervical malignancy; undiagnosed abnormal genital bleeding;
congenital or acquired abnormality of the uterus including fibroids if they
distort the uterine cavity; liver tumour or other acute or severe liver disease;
acute malignancies affecting the blood or leukaemias except when in
remission; recent trophoblastic disease while hCG levels remain elevated;
hypersensitivity to the active substance or to any of the excipients.
Active or previous severe arterial disease, such as stroke or myocardial
infarction is a contraindication when Mirena is used in conjunction with an
oestrogen for HRT use.
Special warning and precautions for use
Before insertion, a complete personal and family medical history should be
taken. Physical examination should be guided by this and by the
contraindications and warnings for use. Pulse and blood pressure should be
measured and a bimanual pelvic examination performed to establish the
orientation of the uterus. The patient should be re-examined six weeks after
insertion and further examinations should be performed where clinically
indicated and adapted to the individual woman rather than as routine
procedure. Prior to insertion pregnancy should be excluded and genital
infection should be successfully treated. Women should be advised that
Mirena does not protect against HIV (AIDs) and other sexually transmitted
disease (please refer to the section below on pelvic infections).
Women should be encouraged to attend cervical and breast screening as
appropriate for their age.
For the treatment of postmenopausal symptoms, HRT should only be
initiated for symptoms that adversely affect quality of life. In all cases, a
careful appraisal of the risks and benefits should be undertaken at least
annually and HRT should only be continued as long as the benefit
outweighs the risk. The contraindications and warnings for the oestrogen
component should also be considered prior to commencing the HRT
Conditions under which Mirena can be used with caution
Should any of the following conditions exist or arise for the first time during
treatment, removal of the system should be considered:
Migraine with aura
Unusually severe or unusually frequent headache
Marked increase of blood pressure
Malignancies affecting the blood or leukaemias in remission
Use of chronic corticosteroid therapy
Past history of symptomatic functional ovarian cysts
Active or previous severe arterial disease, such as stroke or
myocardial infarction (see ‘Contraindications’ when Mirena is used in
conjunction with an oestrogen for HRT use).
Severe or multiple risk factors for arterial disease
Thrombotic arterial or any current embolic disease
Acute venous thromboembolism.
In general, women using hormonal contraception should be encouraged to
give up smoking.
Mirena should be used with caution in postmenopausal women with
advanced uterine atrophy.
Insertion/removal warnings and precautions
As the insertion technique is different from other intrauterine devices,
special emphasis should be given to training in the correct insertion
technique. Instructions for insertion are in the package.
Insertion and removal may be associated with some pain and bleeding. In
case of difficult insertion and/or exceptional pain or bleeding during or after
insertion, physical examination and ultrasound should be performed
immediately to exclude perforation of the uterine corpus or cervix (see also
‘Perforation’). Physical examination alone (including checking of threads)
may not be sufficient to exclude partial perforation.
The procedure may precipitate fainting as a vasovagal reaction, or a seizure
in an epileptic patient. In the event of early signs of a vasovagal attack,
insertion may need to be abandoned or the system removed. The woman
should be kept supine, the head lowered and the legs elevated to the
vertical position if necessary in order to restore cerebral blood flow. A clear
airway must be maintained; an airway should always be at hand. Persistent
bradycardia may be controlled with intravenous atropine. If oxygen is
available it may be administered.
Perforation of the uterine corpus or cervix may occur, most commonly
during insertion, although it may not be detected until sometime later. This
may be associated with severe pain and continued bleeding. If perforation is
suspected the system should be removed as soon as possible; surgery may
In a large prospective comparative non-interventional cohort study in IUD
users (N = 61,448 women), the incidence of perforation was 1.3 (95% CI:
1.1 – 1.6) per 1000 insertions in the entire study cohort; 1.4 (95% CI 1.1 –
1.8 per 1000 insertions in the Mirena cohort and 1.1 (95% CI: 0.7 -1.6) per
1000 insertions in the copper IUD cohort.
The study showed that both breastfeeding at the time of insertion and
insertion up to 36 weeks after giving birth were associated with an
increased risk of perforation (see Table 1). These risk factors were
independent of the type of IUD inserted.
Table 1: Incidence of perforation per 1000 insertions for the entire study
cohort, stratified by breastfeeding and time since delivery at insertion
Breastfeeding at time
Not breastfeeding at
time of insertion
Insertion ≤ 36
weeks after delivery
(95% CI 3.9-7.9;
(95% CI 0.8-3.1;
Insertion > 36
weeks after delivery
(95% CI 0.0-9.1;
(95% CI 0.5-1.1;
The risk of perforation may be increased in women with a fixed retroverted
Re-examination after insertion should follow the guidance given above
under the heading "Medical examination" above, which may be
adapted as clinically indicated in women with risk factors for perforation.
The insertion tube helps to prevent Mirena from contamination with microorganisms during the insertion and the Mirena inserter has been designed
to minimise the risk of infections. In users of copper intrauterine devices
(IUDs), the highest rate of pelvic infections occurs during the first month
after insertion and decreases later. Known risk factors for pelvic
inflammatory disease are multiple sexual partners, frequent intercourse and
young age. Pelvic infection may have serious consequences as it may
impair fertility and increase the risk of ectopic pregnancy. As with other
gynaecological or surgical procedures, severe infection or sepsis (including
group A streptococcal sepsis) can occur following IUS insertion, although
this is extremely rare. For women using Mirena with symptoms and signs
suggestive of pelvic infection, bacteriological examinations are indicated
and monitoring is recommended, even with discrete symptoms, and
appropriate antibiotics should be started. There is no need to remove
Mirena unless the symptoms fail to resolve within the following 72 hours or
unless the woman wishes Mirena to be removed. Mirena must be removed
if the woman experiences recurrent endometritis or pelvic infection, or if an
acute infection is severe.
Complications leading to failure
Symptoms of the partial or complete expulsion of any IUS may include
bleeding or pain. However, a system can be expelled from the uterine cavity
without the woman noticing it. Partial expulsion may decrease the
effectiveness of Mirena. As the system decreases menstrual flow, increase
of menstrual flow may be indicative of an expulsion. A displaced Mirena
should be removed and a new system inserted.
The woman should be advised how to check the threads of Mirena.
If the retrieval threads are not visible at the cervix on follow-up examination
- first exclude pregnancy. The threads may have been drawn up into the
uterus or cervical canal and may reappear during the next menstrual period.
If they cannot be found, they may have broken off, the system may have
been expelled, or rarely the device may be extrauterine after having
perforated the uterus. An ultrasound should be arranged to locate the
device and alternative contraception should be advised in the mean time. If
an ultrasound cannot locate the device and there is no evidence of
expulsion, a plain abdominal X-ray should be performed to exclude an
Mirena usually achieves a significant reduction in menstrual blood loss in 3
to 6 months of treatment. Increased menstrual flow or unexpected bleeding
may be indicative of expulsion. If menorrhagia persists then the woman
should be re-examined. An assessment of the uterine cavity should be
performed using ultrasound scan. An endometrial biopsy should also be
Risk in pre-menopausal women
Because irregular bleeding/spotting may occur during the first months of
therapy in pre-menopausal women, it is recommended to exclude
endometrial pathology before insertion of Mirena.
Risk in post-menopausal women
If the woman continues the use of Mirena inserted earlier for contraception,
endometrial pathology has to be excluded if bleeding disturbances appear
after commencing oestrogen replacement therapy. If bleeding irregularities
develop during a prolonged treatment, appropriate diagnostic measures
should also be taken as irregular bleeding may mask symptoms and signs
of endometrial polyps or cancer.
When to check for pregnancy in women of child bearing potential:
The possibility of pregnancy should be considered if menstruation does not
occur within six weeks of the onset of previous menstruation and expulsion
should be excluded. A repeated pregnancy test is not necessary in
amenorrhoeic subjects unless indicated by other symptoms. In a study in
women who used Mirena for contraception (n=130), oligomenorrhoea and
amenorrhoea were reported in 57% and 16% of women respectively at the
end of the first year of use.
Treatment review advice for Menorrhagia:
Mirena usually achieves a significant reduction in menstrual blood loss in 3
to 6 months of treatment. If significant reduction in blood loss is not
achieved in these time-frames, alternative treatments should be considered.
Other risks during use
The absolute risk of ectopic pregnancy in Mirena users is low. However,
when a woman becomes pregnant with Mirena in situ, the relative likelihood
of ectopic pregnancy is increased. The possibility of ectopic pregnancy
should be considered in the case of lower abdominal pain - especially in
connection with missed periods or if an amenorrhoeic woman starts
bleeding. In a large prospective comparative non-interventional cohort study
with an observation period of 1 year, the ectopic pregnancy rate with Mirena
was 0.02%. In clinical trials, the absolute rate of ectopic pregnancy in users
of Mirena was approximately 0.1% per year. This rate is lower than the rate
of 0.3-0.5 % per year estimated for women not using any contraception.
Women with a previous history of ectopic pregnancy carry a higher risk of a
further ectopic pregnancy.
Since the contraceptive effect of Mirena is mainly due to its local effect,
ovulatory cycles with follicular rupture usually occur in women of fertile age.
Sometimes atresia of the follicle is delayed and folliculogenesis may
continue. These enlarged follicles cannot be distinguished clinically from
Data from clinical trials suggest that ovarian cysts have been reported as an
adverse drug reaction in approximately 7% of women using Mirena,
however some published studies have reported a higher incidence of
ovarian cysts (which could have been influenced by factors including
frequency and criteria of ultrasound scanning, and patient population). Most
of these follicles are asymptomatic, although some may be accompanied by
pelvic pain or dyspareunia. In most cases, the ovarian cysts disappear
spontaneously during two to three months’ observation. Should this not
happen, continued ultrasound monitoring and other diagnostic/ therapeutic
measures are recommended. Rarely, surgical intervention may be required.
Risk in pre-menopausal women
A meta-analysis from 54 epidemiological studies reported that there is a
slightly increased relative risk (RR = 1.24) of having breast cancer
diagnosed in women who are currently using combined oral contraceptives
(COCs), mainly using oestrogen-progestogen preparations. The excess risk
gradually disappears during the course of the 10 years after cessation of
COC use. Because breast cancer is rare in women under 40 years of age,
the excess number of breast cancer diagnoses in current and recent COC
users is small in relation to the overall risk of breast cancer.
The risk of having breast cancer diagnosed in users of progestogen-only
methods (POPs, implants and injectables), including Mirena, is possibly of
similar magnitude to that associated with COC. However, for progestogenonly contraceptive preparations, the evidence is based on much smaller
populations of users and so is less conclusive than that for COCs.
Risk in post-menopausal women
The risk of breast cancer is increased in post-menopausal women using
systemic (i.e. oral or transdermal) hormone replacement therapy (HRT).
This risk is higher with combined oestrogen-progestogen HRT than with
oestrogen-only HRT. The risk of breast cancer when Mirena is prescribed to
provide the progestogen component of HRT is not yet known. The product
information of the oestrogen component of the treatment should also be
consulted for additional information.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal
product is important. It allows continued monitoring of the benefit/risk
balance of the medicinal product. Healthcare professionals are asked to
report any suspected adverse reactions via the Yellow Card Scheme
Low-dose levonorgestrel may affect glucose tolerance, and the blood
glucose concentration should be monitored in diabetic users of Mirena.
Limited experience suggests that Mirena is not suitable for use as a postcoital contraceptive.
Interaction with other medicinal products and other forms of
The metabolism of progestogens may be increased by concomitant use of
substances known to induce drug-metabolising enzymes, specifically
cytochrome P450 enzymes, such as anticonvulsants (e.g. phenobarbital,
primidone, phenytoin, carbamazepine) and anti-infectives (e.g., griseofulvin,
rifampicin, rifabutin, nevirapine, efavirenz). The influence of these drugs on
the contraceptive efficacy of Mirena has not been studied but is not believed
to be of major importance due to the local mechanism of action.
Fertility, pregnancy and lactation
The use of Mirena during an existing or suspected pregnancy is
contraindicated. In case of an accidental pregnancy with Mirena in situ,
ectopic pregnancy should be excluded (see ‘Special warnings and
precautions for use’) and the system must be removed and termination of
the pregnancy should be considered. Removal of Mirena or probing of the
uterus may result in spontaneous abortion. Should these procedures not be
possible, the woman should be informed about increased risk of
spontaneous abortion or premature labour observed during the use of
copper and plastic IUDs. Accordingly, such pregnancies should be closely
monitored. The woman should be instructed to report all symptoms that
suggest complications of the pregnancy, like cramping abdominal pain with
Because of the intrauterine administration and the local exposure to the
hormone, teratogenicity (especially virilisation) cannot be completely
excluded. It can be expected that the systemic hormone exposure of the
foetus through the maternal circulation is lower than with any other
hormonal contraceptive method. Clinical experience of the outcomes of
pregnancies with Mirena in situ is limited. However, the woman should be
informed that, to date, there is no evidence of birth defects caused by
Mirena use in cases where pregnancy continues to term with Mirena in
Levonorgestrel has been identified in the breast milk. About 0.1% of the
levonorgestrel dose is transferred during breast-feeding, but it is not likely
that there will be a risk for the child with the dose released from Mirena,
when it is inserted in the uterine cavity.
There appears to be no deleterious effects on infant growth or development
when using any progestogen-only method after six weeks postpartum.
Progestogen-only methods do not appear to affect the quantity or quality of
breast milk. Uterine bleeding has rarely been reported in women using
Mirena during lactation.
Studies have suggested that in women who discontinue Mirena for planned
pregnancy the pregnancy rate at one year is similar to those who do not use
Undesirable effects are more common during the first months after the
insertion, and subside during prolonged use.
Very common undesirable effects (occurring in more than 10% of users)
include uterine/vaginal bleeding including spotting, oligomenorrhoea,
amenorrhoea (see ‘Pharmacodynamic properties’).
The frequency of benign ovarian cysts depends on the diagnostic method
used (see ‘Special warnings and precautions for use’) but has been
estimated from clinical trial data to occur in 7% of users.
Cases of sepsis (including group A streptococcal sepsis) have been
reported following IUD insertion (see ‘Special warnings and precautions for
When a woman becomes pregnant with Mirena in situ, the relative risk of
ectopic pregnancy is increased.
Cases of breast cancer have been reported in Mirena users.
The following adverse reactions have been reported in connection with the
insertion or removal procedure of Mirena: pain, bleeding and insertionrelated vasovagal reaction with dizziness or syncope. The procedure may
also precipitate a seizure in patients with epilepsy. The removal threads
may be felt by the partner during intercourse.
≥ 1/100 to < 1/10
≥ 1/1000 to < 1/100
≥ 1/10,000 to < 1/1000
(See table opposite)
ATC Code: G02BA03
Pharmacotherapeutic group: Plastic IUD with progestogen
Levonorgestrel is a progestogen used in gynaecology in various ways: as
the progestogen component in oral contraceptives, in hormonal
replacement therapy or alone for contraception in minipills and subdermal
Levonorgestrel can also be administered directly into the uterine cavity as
an intrauterine system. This allows a very low daily dosage, as the hormone
is released directly into the target organ.
The contraceptive mechanism of action of Mirena is based on mainly
hormonal effects producing the following changes:
Prevention of proliferation of the endometrium
Thickening of the cervical mucus thus inhibiting the passage of sperm
Suppression of ovulation in some women.
The physical presence of the system in the uterus would also be expected
to make a minor contribution to its contraceptive effect.
When inserted according to the insertion instructions, Mirena has a
contraceptive failure rate of approximately 0.2% (95% CI: 0.1-0.3) per year
and a cumulative failure rate of approximately 0.7% at 5 years. The failure
rate may increase in case of Mirena expulsion or perforation.
Mirena may be particularly useful for contraception in patients with
excessive menstrual bleeding, and can be successfully used in the
treatment of idiopathic menorrhagia. Results from three comparative studies
indicate that in menorrhagic women, menstrual blood loss decreased by 6294% at the end of three months and by 71-95% at the end of six months of
use. Mirena appears to have similar effects to endometrial
ablation/resection in reducing the menstrual blood loss up to two years.
Menorrhagia caused by submucosal fibroids may respond less favourably.
Reduced bleeding promotes the increase of blood haemoglobin in patients
In idiopathic menorrhagia, prevention of proliferation of the endometrium is
the probable mechanism of action of Mirena in reducing blood loss.
The efficacy of Mirena in preventing endometrial hyperplasia during
continuous oestrogen treatment is the same when oestrogen is
administered orally or transdermally. The observed hyperplasia rate under
oestrogen therapy alone is as high as 20%. In clinical studies with a total of
634 perimenopausal and postmenopausal users of Mirena, no cases of
endometrial hyperplasia were reported up to four years.
Different kinds of bleeding changes (frequent, prolonged or heavy bleeding,
spotting, oligomenorrhoea, amenorrhoea) are experienced by all users of
Mirena. In fertile women the average number of spotting days/month
decreases gradually from nine to four days during the first six months of
use. The percentage of women with prolonged bleeding (more than eight
days) decreases from 20% to 3% during the first three months of use. In
clinical studies during the first year of use, 17% of women experienced
amenorrhoea of at least three months duration.
When used in combination with oestrogen replacement therapy,
perimenopausal users of Mirena may experience spotting and irregular
bleeding during the first months of the treatment. The amount of bleeding
becomes minimal during the first year, and 30-60% of users are totally free
Special precautions for disposal
Mirena is supplied in a sterile pack which should not be opened until
required for insertion. Each system should be handled with aseptic
precautions. If the seal of the sterile envelope is broken, the system inside
should be disposed of in accordance with the local guidelines for the
handling of biohazardous waste. Likewise, a removed Mirena and inserter
should be disposed of in this manner. The outer carton package and the
inner blister package can be handled as household waste.
Procured from within the EU. Product Licence Holder: Quadrant
Pharmaceuticals Ltd, Lynstock House, Lynstock Way, Lostock, Bolton,
BL6 4SA. Repackaged by Maxearn Ltd, Bolton, BL6 4SA.
Date of preparation 30th August 2016
normal, class II
* This frequency is based on clinical trials that excluded breastfeeding
women. In a large prospective comparative non-interventional cohort study
in IUD users, the frequency of perforation in women who were
breastfeeding or had an insertion up to 36 weeks after delivery was
“uncommon” (see section 4.4).
Mirena® Intra-Uterine System
This product is known by the above name, but will be referred to as Mirena throughout the
remainder of the leaflet
Only to be inserted by a trained healthcare professional using aseptic technique.
Mirena is supplied within an inserter in a sterile package which should not be opened until needed
Do not resterilise. As supplied, Mirena is for single use only. Do not use if the inner package is
damaged or open. Do not insert after the expiry month and year shown on the label.
For timing of insertion, please consult the Mirena prescribing information.
Preparation for insertion
Examine the patient to establish the size and position of the uterus, in order to detect any
signs of acute genital infections or other contraindications for the insertion of Mirena and to
Insert a speculum, visualise the cervix, and then thoroughly cleanse the cervix and vagina
with a suitable antiseptic solution.
Use an assistant as necessary.
Grasp the anterior lip of the cervix with a tenaculum or other forceps to stabilise the uterus. If
the uterus is retroverted, it may be more appropriate to grasp the posterior lip of the cervix.
Gentle traction on the forceps can be applied to straighten the cervical canal. The forceps
should remain in position and gentle counter traction on the cervix should be maintained
throughout the insertion procedure.
Advance a uterine sound through the cervical canal to the fundus to measure the depth and
confirm the direction of the uterine cavity and to exclude any evidence of intrauterine
abnormalities (e.g. septum, submucous fibroids) or a previously inserted intrauterine
contraceptive which has not been removed. If difficulty is encountered, consider dilatation of
the canal. If cervical dilatation is required, consider using analgesics and/or a paracervical
IMPORTANT! Should you suspect that the system is not in the correct position, check placement
(e.g. with ultrasound). Remove the system if it is not positioned properly within the uterine cavity. A
removed system must not be re-inserted.
For removal/replacement, please consult the Mirena prescribing information.
Manufactured by: BAYER OY, PANSIONTIE 47, 20210 TURKU, FINLAND.
30 August 2016
Source: Medicines and Healthcare Products Regulatory Agency
Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.