All About the Mirena IUD

Birth control device that contains the hormone levonorgestrel

Mirena is a hormonal intrauterine device (IUD) that is inserted into the uterus for long-term birth control. Mirena continuously releases a low amount of the progestin (levonorgestrel) for up to eight years as a way to prevent pregnancy.

IUD strings
Eduardo Luzzatti BuyA / E+ / Getty Images

Overview

Mirena is a small, T-shaped contraceptive device made of flexible plastic. It measures 32 millimeters (mm) across and down.

The Mirena IUD can protect you against pregnancy for up to eight years, so It is considered to be a long-acting, reversible birth control method.

Your Mirena IUD must be inserted by a qualified healthcare provider. It is also one of the most effective birth control methods available. It is just as effective as a vasectomy.

How It Works

Over a maximum eight-year time period, the Mirena IUD slowly releases a small amount of progestin (levonorgestrel).

Mirena helps to prevent sperm from joining with an egg by affecting how the sperm move. Basically, it interferes with the movement of the sperm toward the egg.

The Mirena IUD can also thicken your cervical mucus. This also makes it more difficult for the sperm to swim. Because this IUD contains progestin, Mirena is slightly more effective than the Paragard IUD when it comes to preventing pregnancy.

How Quickly Does It Work?

The Mirena IUD works immediately if you have it inserted within seven days after the start of your period.

If you have your Mirena inserted at any other time during your menstrual cycle, you will need to use a backup birth control method during the first seven days after insertion. You will have pregnancy protection after that time.

Who Can Use It?

Most people with a vagina can use the Mirena IUD.

The American College of Obstetricians and Gynecologists approve the use of IUDs such as Mirena, Skyla, or Paragard in people with vaginas who have or have never been pregnant, including teenagers.

Advantages 

  • The Mirena IUD can provide continuous pregnancy prevention for up to eight years.
  • This IUD can be removed any time, if desired.
  • It is convenient and hassle-free: Once inserted, you don’t really have to do anything.
  • Mirena can help protect against pelvic inflammatory disease because it thickens cervical mucus and decreases your monthly period flow.
  • The Mirena IUD can improve your sex life because it lets you be spontaneous.
  • It is an eco-friendly birth control method.
  • Mirena is a good alternative option if you can't use estrogen-based birth control or other hormonal methods.
  • After the Mirena IUD is removed, your ability to become pregnant returns quickly.
  • It is a private and discreet birth control method. Nobody can tell if you are using it. 

Non-Contraceptive Benefits

The Mirena IUD can also provide you with certain additional advantages. If you have really painful menstrual cramps, using the Mirena IUD can help manage your pain. Mirena can also reduce the amount of bleeding you have during your period.

People with vaginas who use Mirena may see that their menstrual bleeding is reduced by 90%. This could lower your risk for anemia.

The Mirena IUD is the only hormone-releasing IUD that is approved by the U.S. Food and Drug Administration (FDA) to treat heavy periods for up to five years.

Side Effects

Most people with vaginas do not experience any trouble while using Mirena. Some may have heavy bleeding and cramping during the first few weeks or months after insertion. A healthcare provider can prescribe medication that can lessen these cramps, if needed.

As with any progestin-only birth control method, you may experience some side effects. The good news is that, in most cases, these side effects will go away after the first few weeks to months after the Mirena IUD is inserted.

Serious problems with Mirena are rare. If you do notice any problems, it is important to tell your healthcare provider right away.

Removal

You must have your Mirena IUD removed after eight years, or you can do so sooner if you wish.

You can choose to have another Mirena inserted during the same visit. Never try to remove your Mirena IUD by yourself. It needs to be removed by a medical professional.

Your Mirena IUD may come out on its own; this is most likely to happen during the first few months after insertion or during your period. Most people don't even realize that their Mirena has come out.

Make a habit of checking your Mirena IUD strings at least once a month (between periods) to ensure the device is still in place and protecting against pregnancy.

If you have noticed that your Mirena has come out, you need to contact your healthcare provider to have another one inserted. Your healthcare provider will most likely perform a pregnancy test before inserting a new Mirena IUD.

Your Mirena IUD could also become partially expelled. If this happens, make an appointment so your healthcare provider can fully take out your Mirena (don't try to pull it out yourself), and use backup birth control (like external or internal condoms) while waiting for your appointment.

Associated Costs 

If you have to pay for your own contraception and you plan to use birth control for at least a year or two, an IUD is the least expensive option available. The one-time cost of Mirena, when compared to other contraceptive methods, could save you hundreds of dollars or more over time.

Medicaid may cover the cost of your Mirena IUD.

Check with your private health insurance policy as the Mirena IUD should be covered with no out-of-pocket costs for all non-grandfathered insurance plans.

Effectiveness

The Mirena IUD is one of the most effective reversible methods of birth control available. The Mirena IUD is 99.8%effective. This means that out of every 100 people with vaginas who use Mirena in one year, less than 1 will become pregnant with typical use as well as with perfect use.

Most pregnancies happen when Mirena IUDs slip out without users realizing it.

Even though the chance of pregnancy while using Mirena is extremely low, if it does happen, call your healthcare provider as soon as you realize that you're pregnant.

STI Protection

Mirena offers no protection against sexually transmitted infections. The Mirena IUD does not cause pelvic inflammatory disease or infertility.

Frequently Asked Questions

  • What are the side effects of Mirena?

    The most common side effect of Mirena is irregular bleeding or spotting, which is a normal occurrence in the first few months after insertion. Some people feel discomfort during the first week after placement.

    One serious side effect is pelvic inflammatory disease (PID). The risk is greatest in the first four weeks after insertion, but this is considered rare.

  • How effective is Mirena?

    IUDs like Mirena are more than 99% effective as birth control and a safe option for most people. In many cases, an IUD is designed to last anywhere between three to 10 years. Mirena has been shown to be effective for up to eight years.

  • How much does an IUD cost?

    Mirena costs about $1000 without health insurance coverage. However, there are programs such as Medicaid which can assist or entirely cover the cost. The total cost of an IUD will depend on the type, brand, and whether an insurance plan offers coverage.

  • Does Mirena have hormones?

    Yes, Mirena releases small amounts of a hormone called progestin. It is one of four brands of hormonal IUD that are available in the U.S. The other three include Liletta, Kyleena, and Skyla.

  • Does Mirena cause you to have no period?

    In some cases, it might. The hormones inside Mirena can significantly reduce the amount of bleeding during a period. Having less or no bleeding isn't considered harmful, but be sure to talk to your healthcare provider if you have any concerns about the effects of Mirena.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Bayer HealthCare Pharmaceuticals Inc. Mirena prescribing information.

  2. Centers for Disease Control and Prevention. Effectiveness of family planning methods.

  3. Nelson AL, Massoudi N. New developments in intrauterine device use: focus on the USOpen Access J Contracept. 2016;7:127–141. doi:10.2147/OAJC.S85755

  4. Planned Parenthood. IUD.

  5. Bayer. For women with heavy periods, bleeding may be reduced with Mirena®.

  6. Kailasam C, Cahill D. Review of the safety, efficacy and patient acceptability of the levonorgestrel-releasing intrauterine systemPatient Prefer Adherence. 2008;2:293-302. doi:10.2147/ppa.s3464

  7. Cleveland Clinic. Mirena, Liletta (hormonal IUD).

  8. Mirena. Cost and insurance coverage.

Dawn Stacey

By Dawn Stacey, PhD, LMHC
Dawn Stacey, PhD, LMHC, is a published author, college professor, and mental health consultant with over 15 years of counseling experience.