Levonorgestrel Intrauterine System
Pronunciation: (mih-REE-nuh).
- Generic name
- Levonorgestrel intrauterine system
- Brand names
- Jaydess, Levonova, Mirena, Kyleena, Levosert, Emilia
- Drug class
- Progestin-only intrauterine contraceptive
Availability and supply rules vary by country
Trade names by country:
Australia: · Full directory
What Levonorgestrel intrauterine system is and how it works
Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.
Mechanism of action: how Levonorgestrel intrauterine system works
Mirena releases levonorgestrel directly into the uterine cavity at a rate of approximately 21 mcg/day after the first 24 days, decreasing to about 11 mcg/day after 5 years and about 7 mcg/day after 8 years. Levonorgestrel thickens cervical mucus, inhibits sperm motility and function, suppresses endometrial growth, and may partially inhibit ovulation. The primary contraceptive effect is local, with minimal systemic absorption. (1) (2)
What Levonorgestrel intrauterine system is used for
Prevention of pregnancy (contraception) for up to 8 years.
Prevention of pregnancy (contraception) for up to 8 years. (2)
Treatment of heavy menstrual bleeding, for up to 5 years, in women who choose intrauterine contraception as their method of contraception.
Treatment of heavy menstrual bleeding, for up to 5 years, in women who choose intrauterine contraception as their method of contraception. (2)
Before taking Levonorgestrel intrauterine system
Do not take / not appropriate for
- pregnancy, current PID, uterine or cervical malignancy, unexplained vaginal bleeding, acute liver disease or tumor, and known or suspected breast cancer. (Contraindication) (2)
Tell your clinician about
(2)How to take Levonorgestrel intrauterine system
- General Instructions: Mirena must be inserted and removed by a trained healthcare professional. It is usually placed during your period or within 7 days of starting your period to ensure you are not pregnant.. Adult Dosing: One Mirena device is inserted into the uterus and provides contraception for up to 8 years. For heavy menstrual bleeding, it is also used for up to 5 years.. Pediatric Dosing: Mirena is not recommended for use before menarche. It may be used in adolescents who have started menstruating and require contraception.. Administration: The device is inserted into the uterus during an office procedure. You may experience cramping or discomfort during and after insertion.. When To Stop: Mirena should be removed after 8 years or sooner if you wish to become pregnant, develop contraindications, or experience serious side effects.. Storage: Store unused devices at room temperature, away from moisture and heat. Once inserted, no special storage is needed.
- This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (2)
Missed dose
Mirena is a device, so there are no daily doses to miss. If the device is expelled or you cannot feel the strings, use backup contraception and contact your healthcare provider immediately.
Overdose
Overdose is unlikely as Mirena is a device inserted by a healthcare professional. If multiple devices are inserted or symptoms of overdose occur (severe pain, heavy bleeding), seek immediate medical attention. (2)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.
Changes in menstrual bleeding pattern (unscheduled bleeding, decreased bleeding, or increased scheduled bleeding)
Incidence: Very common (affects roughly a third of users)
Abdominal or pelvic pain
Incidence: Common (about 22.6% of users)
Amenorrhea (periods stopping)
Incidence: Common (about 18.4% of users)
Headache or migraine
Incidence: Common (about 16.3% of users)
Genital discharge or vulvovaginitis
Incidence: Common (about 10.5-14.9% of users)
Acne or breast tenderness
Incidence: Reported; exact frequency not established in the sources reviewed
Ovarian cysts (may be asymptomatic or cause pelvic pain)
Incidence: About 8% of users; most resolve on their own within 2-3 months
Signs of pelvic infection (PID) — fever, unusual pelvic pain, or abnormal discharge
Incidence: Uncommon; highest risk in the first month after insertion
Signs the device may have perforated or become embedded — severe or worsening pelvic pain, especially around the time of insertion
Incidence: Uncommon
Signs the device has been expelled — being able to feel more of the strings than usual, the strings feeling longer or missing, or the device itself being felt or seen
Incidence: About 4.5% of users over 5 years
Serious warnings
Perforation — serious
Symptoms: Perforation: the device can perforate or become embedded in the uterine wall or cervix, most often during insertion; risk is higher with insertion during breastfeeding, within 6 weeks after childbirth, or with a fixed retroverted uterus. Perforation can lead to device migration, adhesions, peritonitis, bowel injury, and loss of contraceptive effectiveness, and may require surgical removal.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Expulsion — serious
Symptoms: Expulsion: partial or complete expulsion of the device can occur (about 4.5% of users over 5 years in clinical trials), sometimes without noticeable symptoms, resulting in loss of contraceptive effectiveness; risk is higher with immediate postpartum insertion or insertion after a second-trimester abortion.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Ectopic pregnancy — serious
Symptoms: Ectopic pregnancy: about half of pregnancies that occur with this device in place are ectopic (outside the uterus), which can cause loss of fertility and is a medical emergency; overall ectopic pregnancy incidence is about 0.1% per year of use. Risk is higher with a prior ectopic pregnancy, tubal surgery, or pelvic infection.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Pelvic inflammatory disease (PID) — serious
Symptoms: Pelvic inflammatory disease (PID): intrauterine devices are associated with an increased PID risk, mainly from organisms introduced at insertion; risk is highest in the first year (especially the first month) after insertion and increases with multiple sexual partners. This device does not protect against HIV or other sexually transmitted infections.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Ovarian cysts — serious
Symptoms: Ovarian cysts: reported in about 8% of users; most are asymptomatic and resolve on their own within 2-3 months, though some cause pain requiring evaluation.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Contraindications on the current FDA label — serious
Symptoms: Contraindications on the current FDA label: known or suspected pregnancy (cannot be used for emergency contraception); a uterine anomaly that distorts the uterine cavity; active PID, or a history of PID unless a subsequent intrauterine pregnancy has occurred; postpartum endometritis or an infected abortion within the past 3 months; known or suspected uterine or cervical cancer; known or suspected breast cancer or other progestin-sensitive cancer; unexplained vaginal bleeding; an untreated acute lower genital tract infection (cervicitis, vaginitis, bacterial vaginosis); acute liver disease or a liver tumor; conditions with increased susceptibility to pelvic infection; a previously placed IUD not yet removed; or known hypersensitivity to any component.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Enzyme-inducing medicines (e.g., rifampin, some anticonvulsants) | No formal drug-drug interaction studies have been conducted with this device. Because its contraceptive effect comes from levonorgestrel released directly and locally into the uterine cavity, the FDA label states this effect is unlikely to be reduced by drug interactions via liver enzyme induction or inhibition — a different, more reassuring position than for systemic hormonal contraceptives (pills, patches, systemic implants), where such interactions are a recognized concern. | (2) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
This device is contraindicated in known or suspected pregnancy and cannot be used for emergency contraception. If pregnancy is diagnosed with the device in place, it is generally removed, because leaving it in place may increase the risk of miscarriage and preterm labor; there is also a risk of septic abortion (with septicemia, shock, and death), a higher likelihood that any pregnancy that does occur is ectopic, and isolated reports of virilization (male-pattern physical changes) in a female fetus after local levonorgestrel exposure. Anyone who suspects they are pregnant with the device in place should contact their clinician promptly. (2)
Breastfeeding
This device may be used while breastfeeding. Only small amounts of levonorgestrel (roughly 0.1% of the maternal dose) are detected in breast milk, and no adverse effects have been reported in breastfed infants from maternal use of progestin-only contraceptives, though isolated cases of decreased milk production have been reported. The risk of the device perforating or becoming embedded in the uterine wall is increased if it is inserted while breastfeeding. (2)
Children
Not recommended for use before menarche (a person's first period). It may be used in adolescents who have started menstruating and require contraception, following the same insertion and monitoring guidance as for adults; this is not a weight- or age-dosed medicine, since a single device is used regardless of age. (2)
Renal_impairment
Contraindicated in acute liver disease or a liver tumor. No renal-impairment-specific guidance was found in the sources reviewed for this pass, consistent with the device's local (not systemic) mechanism of action. (2)
Hepatic_impairment
Contraindicated in acute liver disease or a liver tumor. No renal-impairment-specific guidance was found in the sources reviewed for this pass, consistent with the device's local (not systemic) mechanism of action. (2)
Monitoring
(2)Storage
Store unused devices at 25 degC (77 degF), with excursions permitted between 15-30 degC (59-86 degF), away from moisture and heat. The device is supplied sterile (sterilized with ethylene oxide) for single use only — do not re-sterilize — and should be inserted before the expiry date shown on the label. Once inserted, no special storage is needed.
Professional information
Clinician-facing context only. This section does not replace current product labeling.
General (US label)
Indication: Contraception (up to 8 years) / heavy menstrual bleeding treatment (up to 5 years)
Dose summary: One Mirena intrauterine system (52 mg levonorgestrel) is inserted into the uterus by a healthcare provider. No patient-adjustable dosing applies.
Renal context: No renal-impairment-specific dosing guidance is defined on the label, consistent with the device's local (not systemic) mechanism. (1) (2)
Frequently asked questions
How effective is Mirena at preventing pregnancy?
Mirena is over 99% effective at preventing pregnancy, making it one of the most reliable forms of reversible contraception available.
How soon after insertion does Mirena start working?
If inserted during the first 7 days of your menstrual cycle, Mirena is effective immediately. If inserted at another time, use backup contraception for 7 days.
Can Mirena be used to treat heavy periods?
Yes, Mirena is approved for the treatment of heavy menstrual bleeding in women who choose intrauterine contraception.
What should I do if I cannot feel the Mirena strings?
If you cannot feel the strings or suspect the device has moved or been expelled, use backup contraception and contact your healthcare provider as soon as possible.
Can I get pregnant after Mirena is removed?
Yes, fertility typically returns quickly after Mirena is removed, and most women can become pregnant within a few months.
Does Mirena protect against sexually transmitted infections (STIs)?
No, Mirena does not protect against HIV or other STIs. Use condoms to reduce your risk of infection.
How long can Mirena stay in place?
Mirena can be used for up to 8 years for contraception. For heavy menstrual bleeding, it is approved for up to 5 years.
What happens if I take too much Mirena?
Mirena is an intrauterine system, not a pill, so 'taking too much' in the traditional sense is not applicable. However, if the device is expelled or there are concerns about its function, it's crucial to contact your healthcare provider immediately. Symptoms like severe pain, heavy bleeding, or signs of infection warrant emergency medical attention.
Can I drink alcohol while taking Mirena?
There are no known direct interactions between alcohol consumption and the effectiveness or safety of Mirena. As a progestin-only intrauterine system, its mechanism of action is localized within the uterus and not significantly affected by alcohol. However, it's always advisable to consume alcohol in moderation for overall health.
Is Mirena safe during pregnancy?
Mirena is contraindicated in known or suspected pregnancy and cannot be used as emergency contraception. If pregnancy occurs with Mirena in place, the device is generally removed because leaving it in place may raise the risk of miscarriage, preterm labor, and septic abortion, and any pregnancy that does occur is more likely to be ectopic. You must contact your doctor promptly if you suspect you are pregnant while using Mirena.
What is the mechanism of action of Levonorgestrel intrauterine system?
Mirena releases levonorgestrel directly into the uterine cavity at a rate of approximately 21 mcg/day after the first 24 days, decreasing to about 11 mcg/day after 5 years and about 7 mcg/day after 8 years. Levonorgestrel thickens cervical mucus, inhibits sperm motility and function, suppresses endometrial growth, and may partially inhibit ovulation. The primary contraceptive effect is local, with minimal systemic absorption. (1) (2)
What is the generic name of Levonorgestrel Intrauterine System?
The generic name is Levonorgestrel intrauterine system. It is sold under brand names including Jaydess, Levonova, Mirena, Kyleena, Levosert, Emilia.
What class of drug is Levonorgestrel intrauterine system?
Levonorgestrel Intrauterine System is classed as: Progestin-only intrauterine contraceptive.
References
- MedGuideGlobal Medicine Record: Mirena (levonorgestrel-releasing intrauterine system)MedGuideGlobal · Internal/Global · accessed 2026-08-06 · source 1
- MIRENA (levonorgestrel-releasing intrauterine system) — full prescribing informationU.S. Food and Drug Administration (DailyMed) · United States · accessed 2026-08-06 · source 2
- Levonorgestrel Intrauterine System — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 3
- Levonorgestrel intrauterine system — RxNorm normalized drug concept (RXCUI 1856515)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 4
Brand names by country
Single-ingredient Levonorgestrel intrauterine system names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.