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Overview: Mirena is an intrauterine device (IUD), a form of birth control, that is inserted into the uterus to prevent pregnancy for up to eight years, or to prevent pregnancy and treat heavy menstrual bleeding for up to five years. Common side effects include changes in menstrual bleeding, stomach or pelvic pain, and headache. Serious side effects are rare, but can include infections or uterus problems.

Uses

What is Mirena used for?

Mirena (levonorgestrel) is an intrauterine device (IUD) that is commonly used to prevent pregnancy for up to eight years. It can also be used to prevent pregnancy and treat heavy menstrual bleeding for up to five years.

Mirena may also be used for other conditions as determined by your healthcare provider.

Learn more about birth control with Mirena.

There are other levonorgestrel intrauterine devices (IUDs) available. See Kyleena, Liletta, and Skyla for more information.

How does Mirena work (mechanism of action)?

Mirena works by slowly releasing a progestin hormone, called levonorgestrel, into the uterus. It may prevent pregnancy by thickening the mucus in your cervix to block sperm from reaching the uterus, affecting sperm so they can not survive or function properly. It may also change the lining of your uterus to make it less likely for a pregnancy to happen.

How is Mirena supplied (dosage forms)?

Brands and other names

  • Mirena

Dosage forms and strengths

Mirena is available as an intrauterine device (IUD) that is inserted by a healthcare provider.

How should I store Mirena?

Mirena is usually inserted by a healthcare provider during an in-office visit or in the hospital. You will not store it at home.

Side Effects

What are the most common side effects of Mirena?

The most common side effects of Mirena are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Changes in menstrual bleeding (see below) 
  • Stomach or pelvic pain 
  • Lack of periods (amenorrhea)
  • Headache or migraine
  • Vaginal discharge
  • Inflammation or infection of the outer parts of the vagina (vaginitis)
  • Ovarian cysts (see below)

There may be other side effects of Mirena that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of Mirena?

While less common, the most serious side effects of Mirena are described below, along with what to do if they happen.

Severe Allergic Reactions. Mirena may cause allergic reactions, which can be serious. Get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Severe Infection. Mirena can increase your risk of a severe infection or sepsis within the first few days after the device is inserted. Call your healthcare provider right away if you have severe pain or fever.  

Uterus Problems. Mirena may go into the wall of the uterus (become embedded) or go through the wall of the uterus (perforation). This increases your risk of pregnancy. It also increases your risk of infection and damage to other organs. The risk of perforation is higher if Mirena is inserted after you have recently given birth or if you are breastfeeding. Tell your healthcare provider right away if you cannot feel the threads of the device inside your vagina or if you have pain or bleeding that gets worse after Mirena is inserted. 

Expulsion. Mirena may come out of the uterus by itself, which is called expulsion. The risk of expulsion is higher if Mirena is placed right after you deliver a baby or have a second-trimester abortion. If Mirena comes out, you will be at higher risk of pregnancy. Tell your healthcare provider right away if you cannot feel the threads of Mirena inside your vagina or if you have pain or bleeding that gets worse after Mirena is inserted.

Ovarian Cysts. Mirena may cause cysts to form on your ovaries. Some ovarian cysts are harmless and go away on their own, while others may grow and cause bloating, swelling, or pain in your lower belly. Get emergency help right away if you have any of the following symptoms that an ovarian cyst has burst.

  • Sharp, sudden pain in your lower belly or back
  • Abnormal spotting or bleeding
  • Pain with fever and throwing up
  • Dizziness, weakness, or feeling faint
  • Fast breathing (hyperventilation)

Changes in Menstrual Bleeding. Mirena can cause your period to become irregular, longer, and heavier than usual at first. It can also cause spotting or light bleeding between periods, especially in the first three to six months after placement. For some people, periods will stop after Mirena has been placed for a while. Call your healthcare provider right away if bleeding remains heavier or lasts longer than usual, or if it increases after it has been light or absent for a while. 

Pelvic Inflammatory Disease. Mirena can increase the risk of pelvic inflammatory disease (PID), which is an infection that can affect the uterus, ovaries, or fallopian tubes. Bacteria that cause pelvic inflammatory disease can get into your body when Mirena is inserted. Call your healthcare provider right away if you have any of the following symptoms of PID.

  • Pain in your lower belly or pelvis
  • Heavy vaginal discharge that is discolored and has a bad smell
  • Heavy bleeding during your period or bleeding between periods
  • Pain or bleeding during sex
  • Chills or fever
  • Pain when your pee or problems peeing
  • Sores on your genitals

Pregnancy Problems. If you become pregnant while using Mirena, you may be at higher risk of miscarriage, infection, and early labor or delivery. You may also be at higher risk of that pregnancy being outside the uterus (ectopic pregnancy). With ectopic pregnancy, as the fertilized egg grows, it can burst (rupture) and cause life-threatening bleeding and death. Call your healthcare provider right away if you think you might be pregnant or have any of the following symptoms. 

  • Pain in your lower stomach or vomiting
  • Sharp belly cramps 
  • Unusual vaginal bleeding or discharge
  • Pain on one side of your body
  • Dizziness or weakness
  • Pain in your shoulder, neck, or rectum
  • Fever, chills, or flu-like symptoms

Warnings & Precautions

Who should not use Mirena?

Allergies to Ingredients. People who are allergic to any of the following should not use Mirena.

  • Mirena
  • Levonorgestrel
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in Mirena.

Pregnancy. Do not use Mirena if you are pregnant or think you might be pregnant. If you become pregnant, contact your healthcare provider right away. See the Pregnancy section for more details.

Uterus Problems. Mirena should not be used if you have bleeding from the uterus for an unknown reason, or if you have problems that change the shape of your uterus, such as fibroids. Mirena may not work as well if you have these conditions.

Pelvic or Genital Infections. Mirena should not be used if you are at high risk of pelvic inflammatory disease (PID), which is an infection that can affect the uterus, ovaries, or fallopian tubes. It should also not be used if you have recently had an infection of the uterus after a pregnancy or abortion, or if you currently have an infection of the uterus, ovaries, fallopian tubes, cervix, or vagina. The infection should be treated before using Mirena.

Cancer. Mirena should not be used if you have or have had breast, uterine, or cervical cancer. Some cancers are sensitive to hormones and could get worse if you use Mirena.

Liver Problems. Mirena should not be used if you have liver disease or a liver tumor. If there is a concern about the health of your liver, your healthcare provider may do tests to determine if it is working well enough to use this medicine.  

Another Intrauterine Device (IUD). Mirena should not be used if you already have an intrauterine device (IUD) inside your uterus. The other device must be removed before Mirena can be placed.

What should I know about Mirena before using it?

Mirena is an intrauterine device (IUD) that is inserted into the uterus by your healthcare provider at a medical facility. It will be removed or replaced after five or eight years, depending on why you are using it, but it can be removed at any time.

Mirena does not protect you from HIV, AIDS, or other sexually transmitted diseases (STDs). 

Depending on when Mirena is inserted during your menstrual period, or if you are switching from another form of birth control, you may need to use backup birth control (such as condoms or spermicide) after Mirena is placed. Ask your healthcare provider whether you need to use backup birth control and for how long. 

Tell your healthcare provider right away if you have intense pain, bleeding, or dizziness 30 minutes or more after Mirena is inserted. It may need to be removed or replaced. 

Check that Mirena is in place by feeling the threads inside the vagina at least once a month. Talk with your healthcare provider if you have questions about how to do this. 

If you think Mirena has fallen out of your uterus (expulsion) or is out of place, call your healthcare provider right away and use backup birth control (such as condoms or spermicide) until Mirena can be replaced. 

Be extra careful when changing tampons or menstrual cups so that you do not accidentally pull the Mirena threads. Call your healthcare provider right away if you think you have pulled Mirena out of place. 

Make sure to keep all follow-up appointments with your healthcare provider. They will use these appointments to check that Mirena is in the right position. 

You may need special X-rays or other imaging to check whether Mirena is in place, or to help find the device when it is time to take it out. Depending on the exact position of the device, removal may be difficult and may require surgery. Talk to your healthcare provider if you have questions.

What should I tell my healthcare provider before using Mirena?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if Mirena is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your healthcare provider if you have or have had any of the following.

  • Heart problems, heart attack, or stroke
  • Problems with blood clotting 
  • High blood pressure (hypertension)
  • Recently had a baby 
  • Severe headaches or migraine 
  • HIV/AIDS or another sexually transmitted disease (STD)
  • Multiple sexual partners or your partner has multiple sexual partners
  • Immune system problems
  • Substance use disorder (specifically injectable drugs)
  • Liver problems or yellowing of your skin or eyes (jaundice)
  • History of cancer
  • Unexplained vaginal bleeding
  • Conditions that affect the shape your uterus, such as fibroids

Other Medicines and Supplements. Mirena may interact with other medicines and supplements. Before using Mirena, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. Do not use Mirena during pregnancy. Using Mirena while you are pregnant may cause complications during pregnancy. If you become pregnant or think you might be pregnant while using Mirena, contact your healthcare provider right away.

Breastfeeding. Mirena passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should use Mirena while breastfeeding.

How can I get more information about Mirena?

For more information about Mirena, you can visit the manufacturer’s website at www.mirena-us.com or call them at 888-842-2937.

Interactions

Does Mirena interact with foods or drinks?

There are no known interactions between Mirena and foods or drinks.

It is unknown if drinking alcohol will affect Mirena.

Does Mirena interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are taking a blood thinner, which is a medicine used to treat or prevent blood clots.

This may not be a complete list of medicines that can interact with Mirena. Always check with your healthcare provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much Mirena?

If you or someone else has used too much Mirena, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of Mirena?

Mirena is inserted by a healthcare provider and left in place for up to eight years. If it has been in place for too long or has come out of place, avoid sexual intercourse or use a backup birth control (such as condoms or spermicide) and contact your healthcare provider right away.

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