All About the Mirena IUD

The Levonorgestrel IUD

Mirena IUD
Mirena IUD. Photo © Dawn Stacey

The Mirena IUD is a hormonal intrauterine device that is inserted into the uterus for long-term birth control. Mirena releases a low amount of the progestin, levonorgestrel, continuously over a 5-year period as a way to prevent pregnancy.

The Low-Down on the Mirena IUD

Mirena is a type of IUD. It is a small, "T-shaped" contraceptive device made of flexible plastic. It measures 32mm across and down. The Mirena IUD is growing in popularity because it can protect you against pregnancy for up to 5 years, so It is considered to be a long-acting, reversible birth control method.

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

How Mirena Works

Over the 5 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 After Insertion Does the Mirena IUD Work?

The Mirena IUD is works immediately if you have it inserted within 7 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 back-up birth control method during the first week (7 days) after insertion.

You will have pregnancy protection after these 7 days.

Who Can Use Mirena?

According to Bayer HealthCare Pharmaceuticals, the manufacturer of Mirena, the Mirena IUD is meant to be used by women who:

  • Have had at least 1 child.
  • Are in a stable, committed relationship.
  • Have no risk or history of ectopic pregnancy or pelvic inflammatory disease.

    BUT — you should know that most women can use the Mirena IUD.

    The manufacturer provided these recommendations for Mirena use because the research on the Mirena IUD that was used — in order to get FDA approval — was conducted on women who had at least one child.

    The American College of Obstetricians and Gynecologists recommends that both women who have not given birth as well as teenagers could benefit from IUD use (either Mirena, Skyla, or ParaGard). You may also be relieved to know that many doctors have been inserting the Mirena IUD in all types of women for year (despite the manufacturer's guidelines).

    Advantages of Mirena

    • The Mirena IUD can provide continuous pregnancy prevention for 5 years — but it can also be removed anytime within that 5-year period.
    • 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 who estrogen-based birth control or other hormonal methods.
    • After the Mirena IUD is removed, your fertility (ability to become pregnant) returns quickly.
    • It is private and discreet birth control method. Nobody can tell if you are using it! 

    The Mirena IUD Also Offers 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 lower your pain. Mirena can also reduce the amount of bleeding you have during your period.

    • Women who use Mirena may see that their menstrual bleeding is reduced by 90 percent.
    • In about 20 percent of Mirena users, their perod stops altogether within one year. This could lower your risk for anemia.

    The Mirena IUD is also the only FDA-approved birth control method that can be used to treat heavy menstrual bleeding.

    Mirena IUD's Side Effects:

    Most women do not experience any trouble while using Mirena. Some women may have heavy bleeding and cramping during the first few weeks or months after insertion — but doctors can prescribe medication that can lessen these cramps.

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

    Removal of Your Mirena IUD

    After your 5 years are up, you must have your Mirena IUD removed. 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. Also know that you can have your Mirena removed anytime before the 5-year period ends.

    • Your Mirena IUD may comes out on its own (this is most likely to happen during the first few months after insertion or during your period). Most women don't even realize that their Mirena has come out. This is why it you should make a habit of checking your Mirena IUD strings at least once a month (between periods) — this will let you know that your Mirena is still in place.
    • If you have noticed that your Mirena has come out, you need to contact your doctor to have another one inserted. Your doctor will most likely perform a pregnancy test first — just to make sure that you are not pregnant, before inserting a new Mirena IUD.
    • Your Mirena IUD could also become partially expelled. If this happens, call your doctor, and use a a back-up birth control method (like condoms). Make an appointment, so your doctor can fully take out your Mirena (don't try to pull it out yourself). You can have another Mirena IUD inserted at that time.

    Costs Associated with Mirena

    If you have to pay for your own contraception and you plan to use birth control for at least 1 to 2 years, 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.

    The total cost for Mirena may be up to $750. This includes the cost of the exam, the actual Mirena IUD, insertion, and any follow-up visits. may cost up to $750. Medicaid may cover the cost of your Mirena IUD. You should 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.

    Mirena IUD Effectiveness

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

    Be Aware: Most pregnancies happen to Mirena users when their IUDs slip out without them realizing it. Even though the chance of pregnancy while using Mirena is extremely low, if it does happen, call your doctor as soon as realize that you're pregnant.

    STD Protection

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


    Whaley NS, Burke AE. "Intrauterine contraception." Women's Health. 2015 Nov; 11(6):759-767. Full article accessed via private subscription.

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