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    Mirena Side Effects

    As one of the most effective forms of birth control available, many women opt for Mirena to safeguard against pregnancy and to help treat other conditions. At, we have done all of the research you need to help decide whether this IUD or another form of birth control is right for you.

    Quick Overview

    When comparing birth control options, many women like to look for a solution that’s quick and efficient, as well as one they don’t have to worry about on a daily basis.

    There are only a few choices that don’t involve daily or weekly doses: the Depo-Provera injection and the intrauterine device, or IUD. There are several brands of IUDs on the market, with Mirena being one of five FDA-approved options.

    In order to get fitted with Mirena, it’s necessary to visit your gynecologist, who will then, through a series of tests and/or questions determine whether it’s a viable option. The good thing about Mirena is that it’s suitable for premenopausal women of varying ages, including teenagers.

    While this IUD is primarily used to protect against pregnancy, your doctor may also prescribe it to help with other conditions such as excess cramping, heavy menstrual bleeding, endometriosis, anemia and fibroids. It can help relieve pain as well as slow down the blood flow, making it a good choice for women who have tried other medications with little to no effect.

    How Does Mirena Work?

    The Mirena IUD is a t-shaped, plastic device that’s inserted directly into the uterus. After insertion, it slowly releases levonorgestrel, a type of progestin, at the rate of 20 mcg per day.

    It’s good for up to 5 years, after which the progestin amount decreases by half to 10 mcg per day. At this point, it needs to be replaced in order to keep its efficacy.

    The hormone releases locally into the uterus, which means unlike the pill, patch or injection, a very small amount will make it into your bloodstream.

    This hormone helps to thicken up your cervical mucus to make it difficult for sperm to pass through and also thins the uterine lining, making it difficult for a fertilized egg to implant itself. It also works by partially suppressing ovulation, decreasing the chances of an egg releasing each month.

    The t-shape is effective in blocking sperm that makes it through your cervix from reaching the fallopian tubes. Overall, less than 1 percent of women who use Mirena become pregnant each year.

    What Are Some Common Mirena Side Effects?

    Like all prescriptions, it’s not uncommon to feel some side effects after the Mirena IUD is implanted. They may appear immediately, or you may experience them within the first several days or weeks after insertion. Common side effects include, but are not limited to:

    • Spotting between periods
    • Missed periods
    • Pelvic, abdominal or back pain
    • Dizziness
    • Nausea, sometimes to the point of vomiting
    • Bloating or weight gain
    • Acne
    • Ovarian cysts
    • Skin irritation or rash
    • Puffiness in the hands, feet, ankles or face
    • Depression or other mood changes

    You may experience several or none of these effects, depending on how your body reacts to the device. Typically, the symptoms pass within a few weeks, but if they continue to persist, speak with your gynecologist about any concerns that you might have.

    Are the Side Effects Immediate?

    While not all of the side effects are immediate and everybody’s body reacts differently, there are some symptoms you may experience during the implantation. These include dizziness, to the point where you may feel faint, slight discomfort and pain, and bleeding.

    These should subside within 30 minutes after placement, and your doctor may keep you in the office until then for monitoring.

    Rare Mirena Side Effects

    While uncommon, rare Mirena side effects do occur in some women and knowing what these adverse reactions are can help you decide whether you need to seek immediate medical attention. If you experience any of these, call your doctor right away or head to the emergency room if your doctor is not available:

    • Blood clots in arteries, deep vein thrombosis
    • Strep A infection
    • Embolism of the lung
    • Pelvic inflammatory disease (PID)
    • Ectopic pregnancy
    • Sepsis
    • Stroke
    • Breast cancer
    • Hives
    • Expulsion of device

    You may not be able to tell if you’re having one of these reactions, but pay close attention to your symptoms. If anything feels off or different, it’s definitely a cause for concern and it’s best to err on the side of caution.

    More Serious Mirena Side Effects

    With Mirena you might experience adverse reactions that aren’t common, but don’t fall into the rare category, either. They do warrant a call or visit to your gynecologist, however. These serious side effects include:

    • Anemia
    • Ovary enlargement
    • Rash or itching
    • Lack of interest in sexual intercourse
    • Excessive hairiness or hair loss
    • Cervical inflammation
    • Painful menstruation cycles
    • Eczema

    This is not a comprehensive list, so if you experience any symptoms that are not on this list, let your healthcare professional know so you can discuss your concerns.

    Are There Long-Term Side Effects or Harm Caused by Mirena Use?

    Some women have experienced the Mirena IUD migrating and in some cases, even piercing the uterine wall and becoming embedded in the surrounding tissue or even in the pelvic area.

    Class-action lawsuits have been filed in which women have had the device migrate through a fallopian tube, requiring surgery to remove the IUD. In some instances, fertility was affected, while others ended up with severe pain and infection as a result of the migration.

    Mirena’s Drug Identification Number

    Every drug on the market has a unique identification number that makes it easy for the FDA to track. Mirena’s unique ID is NDA 021225 S-031.

    Mirena Dosage

    There is only one dosage of Mirena, and it’s the same for everyone who uses it. The IUD contains 52 mg total of LNG that disburses over 5 years. It contains no estrogen, so those with estrogen sensitivities may find it a better solution than pills, injections or patches.

    Efficacy for Pregnancy

    With a 99 percent efficacy rate, Mirena is one of the most effective forms of birth control available on the market. Only 1 percent of women who use it become pregnant each year.

    Is Mirena Right for You?

    There are a variety of factors that you should take into consideration when it comes to Mirena. Everybody’s body is different so you may be more or less susceptible to the side effects that occur. Some choose Mirena because of its low hormone content, which can result in fewer side effects.

    If you have difficulty remembering to take a pill or apply the patch, you might benefit from the easy care that comes with the IUD. Additionally, it lasts for up to 5 years or until you’re ready to conceive, at which point you can either replace it or have it removed altogether.

    Unlike the other forms of hormonal birth control, you don’t have to wait for your cycles to regulate before you begin trying to conceive. Many women get pregnant immediately after having the IUD removed.

    When to Consult Your Doctor/OBGYN

    During the course of your use of Mirena, there may be certain conditions or events that require a consultation.

    If you become pregnant while the device is inserted, it’s important to notify your gynecologist right away. They will need to remove the device, which carries the risk of miscarriage. Your doctor can discuss your options with you should pregnancy occur.

    If you feel that the device is no longer in place, or has migrated, it’s important to contact your physician right away. They can do an internal exam or an ultrasound to view the location of the IUD and recommend any further steps if it has, indeed, moved.

    While you have a Mirena device implanted, it’s important to do monthly checks to make sure that the strings are still in place, this means the device hasn’t moved. If you can no longer feel the strings, it may mean that the IUD has migrated. A call or visit to your doctor can determine if further action is necessary.

    Risks of Mirena

    The risks associated with Mirena tend to vary from person to person. Many use the IUD without any adverse effects other than those experienced immediately after implantation.

    Perforation and embedding into the uterine or pelvic tissue are minor risks, but they do happen, so it’s important to know what signs to look for.

    Some women who use Mirena will experience an ectopic pregnancy, one that occurs within the fallopian tube. This is a medical emergency and requires surgery to prevent further damage.

    One thing to be aware of is that while Mirena is an effective form of birth control, it’s not in any way, shape or form, meant to protect against STDs or STIs.

    Do Not Use Mirena If: 

    In addition to its interactions with specific medication classes listed below, there are specific conditions where you should avoid using Mirena.

    If you’re currently pregnant, your doctor will not insert the device. While it uses the same hormone as Plan-B, Mirena is not meant to terminate a pregnancy that’s already in progress.

    If you’ve had certain kinds of cancers, such as breast, cervical or uterine cancer, your doctor will likely avoid any type of hormonal birth control because certain types of cancer may be hormone-sensitive, which can trigger growth.

    Additionally, if you’re particularly susceptible to infections or have had liver disease, Mirena is not recommended.

    Mirena Interactions

    Like all drugs, there are specific interactions that Mirena users should be aware of, which is why it’s important to give your doctor a full list of any medications or supplements you might currently be taking. A partial list of those that may interact negatively with Mirena includes:

    • Steroids
    • Blood thinners such as warfarin
    • Insulin
    • St. John’s Wort
    • Sleep aids

    If you’re not sure if the medication you’re taking will interact with the IUD, speak with your doctor.

    What Other Drugs and Treatments Are There?

    If you’re looking for a contraceptive and you’re not sure if Mirena is for you, or your doctor has said that you’re not a good candidate for the device, there are other options. You can take birth control pills, use the patch or even get the shot.

    All of these use estrogen, progestin or a combination thereof. You can also avoid hormonal contraceptives by getting fitted for a diaphragm by your gynecologist, or opting to use condoms and spermicide.

    How Many Cycles of Mirena Should You Try Before Moving On?

    Mirena isn’t administered in cycles, but you should know within the first couple of days or weeks whether or not the device is a good fit for you. In the beginning, there will likely be a little discomfort as you get used to its placement, but there should be no pain.

    The good news is that if you change your mind about the IUD, whether because of discomfort or you want to try a different birth control method, it’s a removable solution that your doctor can handle with a quick visit to the office.