What Is Mirena?
Mirena is a hormonal intrauterine device (IUD) made by pharmaceutical giant, Bayer Healthcare which was approved in 2000 in the U.S. It is implanted in the uterus and left in place for up to five years. Mirena is made of a type of plastic, known as medication-eluting plastic, which contains the contraceptive hormone levonorgestrel.
Once implanted in the uterus, the flexible device expands to form a “T shape” which allows it to remain in the uterus. Over a 5-year period, the plastic will slowly release levonorgestrel into the uterus to prevent pregnancy by making the uterus inhospitable to a fertilized egg.
Mirena is said to be over 99% effective at preventing pregnancy but may cause side effects. Most side effects are mild to moderate and will go away with time, but others may be serious or even life-threatening.
How Does Mirena Work?
Levonorgestrel is a progestin hormone used for birth control that is usually taken by mouth as an oral contraceptive. It has also been used in other birth control devices such as Norplant and in birth control patches. Mirena is constructed of a type of plastic that is embedded with levonorgestrel to be released slowly over a long period of time, directly into the uterus at a rate of 20mcg/day.
Levonorgestrel in Mirena released into the uterus works by:
- Altering or thinning the uterine wall
- Thickening cervical mucus to prevent any sperm from entering the uterus
- Decreasing the survival rate of sperm
It may also prevent ovulation due to systemic or body-wide absorption of levonorgestrel, similar to the way oral contraceptives and other levonorgestrel devices work.
Because Mirena releases levonorgestrel into the uterus rather than into the bloodstream, Mirena uses a smaller amount of hormone than birth control pills, implants, or patches which may reduce certain side effects, however, because it is implanted into the uterus, it causes other risks.
How Is Mirena Implanted?
Mirena is implanted by a physician and will last up to five years. When the woman wishes to remove it or it is time for replacement, the removal must also be done by a healthcare provider.
Implantation of Mirena is performed through a special tube-like device where it is inserted through the cervix. Once in place, flaps on the IUD will expand and hold the device in the uterus to begin releasing hormones. A string is left in place, protruding through the cervix which will allow the recipient to check to ensure that the device is present and will later allow for removal.
Mirena is removed by pulling the attached string, which causes the flexible arms to bend to allow the device to slide out of the cervix. In some cases, however, the device can migrate or move out of the uterus or become implanted in the uterine wall, or to perforate the uterus and other abdominal organs. This will require surgical removal. Surgical removal could lead to permanent damage.
Why Is Mirena Used?
Mirena is used primarily as a long-lasting form of birth control. However, that’s not the only reason women use Mirena. It’s frequently prescribed to treat health conditions such as:
- Heavy periods
- Period pain
- Abnormal uterine lining growth
What Is the History of Mirena?
The IUD became widely available in the U.S. in the 1950s when thermoplastics allowed for easy insertion and removal of flexible plastic. Their popularity increased in the 1960s with the introduction of the copper IUD and by 1973, an estimated 10% of women using birth control had an IUD.
Unfortunately, one of the most popular devices on the U.S. market had a serious design flaw. It had a porous monofilament string which allowed for bacteria to grow on the device, resulting in thousands of infections, hospitalizations, septic abortion events, and at least 5 deaths.
The Dalkon Shield was withdrawn from the U.S. market in 1975 but sales of other IUDs in the U.S. plummeted as well. By the mid-1980s, more than 300,000 lawsuits had been filed against A.H. Robins, manufacturer of the Dalkon Shield, and all other manufacturers simply quit making their devices.
Outside of the U.S. women had continued to use IUDs as a preferred contraceptive method and the first hormone-emitting device, the progenitor of Mirena, was introduced to Europe in the mid-80s. Its introduction to the U.S. market in 2000 brought a renewed popularity for women who wanted longer-term birth control. The first hormonal IUD, Progestasert was withdrawn only a year after its introduction. Mirena was the only available hormonal IUD in the US until 2013 when the FDA approved Skyla, a lower level levonorgestrel IUD that is only good for three years.
Mirena is used by over 150 million around the world. In the U.S., about 5 percent of women who use contraceptives, use IUDs. Women living outside the US are at least twice as likely to use an IUD. In 2009 Mirena was approved to treat heavy menstrual bleeding in women already using an intrauterine device.
What Are the Side Effects of Mirena?
Because Mirena is a hormonal birth control method, some side effects are related to the hormone. In addition, however, Mirena is a medical device that is implanted in the uterus and may cause complications relating to the device.
The most common side effects of Mirena are caused by the hormone, levonorgestrel, which is released from the device into the uterus. As the hormone levels produced by the device are lower than other forms of hormonal contraceptives, most side effects are mild to moderate and will go away after a period of time.
Most new Mirena users experience some changes in their menstrual cycle with irregular bleeding and spotting. Many will experience lighter periods and 1-in-5 users will stop having a menstrual period at all within the first year. Other mild side effects include:
- Headaches or migraines
- Acne development
- Weight increase
- Feeling bloated
- Mood changes or depression
- Vaginal discharge
- Tenderness or pain in the breasts
- Pelvic pain during periods
- Non-cancerous cysts in the ovary
More severe side effects of Mirena can be permanently damaging or even life-threatening.
What Are the Complications of Mirena?
Like all medications, the hormone in Mirena may cause side effects, mainly caused by localized hormonal action when medication is released in the uterus. In some cases, however, because the hormone is contained in an implanted medical device, complications can be severe. Many women have suffered serious and potentially life-threatening side effects after receiving Mirena and its manufacturer, Bayer Healthcare has faced thousands of lawsuits over Mirena’s side effects.
Possible complications that are related to Mirena include:
- Device expulsion
- Organ Perforation
- Pelvic Inflammatory Disease (PID)
- Spontaneous abortion
- Septic abortion
- Ectopic pregnancy
What Is Bleeding?
Mirena has a number of side effects, some of which can be severe, including bleeding which is the most common side effect of the IUD. In most cases, Mirena-associated bleeding will go away after the first 3 to 6 months. In some patients, however, irregular bleeding may continue after the adjustment period.
Excessive bleeding due to Mirena may be severe enough that surgery will be required to remove the device. Injuries caused by Mirena IUD, including some that may be related to bleeding have also resulted in complications including infertility.
What Bleeding Patterns Can Occur with Mirena?
Bleeding patterns associated with Mirena:
- Irregular bleeding
- Heavy bleeding
- Continuous bleeding
- Frequent menstruation
- Oligomenorrhea or infrequent menstruation
- Amenorrhea or absence of menstruation
Irregular bleeding may also mask the development of other conditions such as endometrial polyps or cancer. Irregular bleeding of any type should be reported to a physician and severe bleeding should be treated as an urgent condition.
Patients who experience oligomenorrhea or amenorrhea should be monitored for the first year after an IUD is implanted to ensure it does not result in pregnancy. Up to 20% of women who receive Mirena may become amenorrhoeic in the first year but should keep watch for pregnancy and other gynecological changes.
What Complications Can Arise from Bleeding?
The U.S. Food and Drug Administration has received over 45,000 reports of women suffering from IUD-related bleeding complications, ranging from minor to life-threatening. Mirena bleeding may be associated with the continuous release of hormone medication but it may also be caused by other device complications including:
- Device migration into the abdomen
- Perforation (puncturing) of the intestinal wall
- Embedding in the uterine wall
- Ovarian cysts
- Pregnancy resulting in a miscarriage
- Endometrial changes
What Is Device Expulsion?
Mirena may be spontaneously expelled from the uterus. About six percent of Mirena users experience expulsion. This may cause tissue tearing or other damage and result in bleeding. Symptoms may include bleeding, spotting, cramping, and pain during sexual intercourse. A routine check of the device string may indicate a shorter, lengthened, or absent string. A woman who experiences expulsion will not be protected from pregnancy. Women without a child have a higher risk of expulsion of the Mirena device.
What Is Migration?
Mirena is intended to be implanted in the uterus and left in place for a period of 5 years but in some patients, the device becomes unseated and “migrates” to another area, where it may cause serious damage including organ perforation. Most commonly, when Mirena migration occurs, the device travels further into the uterus where it may erode and may cause perforation of the uterine wall.
Women who use Mirena within six months after birth may be more likely to experience device migration.
What Are the Signs Your IUD Has Moved?
An IUD may have migrated or been expelled if you experience any of these symptoms:
- You or your partner can feel the IUD
- You or your partner cannot feel the IUD strings
- The strings are longer than normal
- The strings are shorter than normal
- Abnormal discharge
- Abnormal bleeding
- Heavy bleeding
What Is Organ Perforation?
If the device travels through the uterine wall and into the abdominal cavity, it may result in the perforation of reproductive organs like the cervix, ovaries, or fallopian tubes or may damage abdominal organs such as the bladder, intestines blood vessels, kidney, or other organs. This can result in serious pain and infection.
Mirena migration and organ perforation will generally require surgery to remove the device, control bleeding, and repair or reconstruct damaged tissues. If the reproductive organs have been significantly affected, future fertility may be limited. Some women may also require multiple surgeries to locate and remove the device and repair damage to organs and other tissue. Patients with organ perforation have also developed scar tissue and chronic pain which is not easily treated.
What Are the Symptoms of Organ Perforation?
Though Mirena is an effective birth control method for most women, it is estimated as many as 1 in 500 insertions may result in uterine perforation when the device becomes unseated and migrates.
If the device has penetrated all the way through the uterine wall, the device may damage other reproductive organs such as the cervix, fallopian tubes, and ovaries. It may also perforate the abdominal wall, bladder, kidneys, or intestines and may pose a serious risk to the patient due to hemorrhage or uncontrolled internal bleeding.
Common symptoms of Mirena device migration and organ penetration can include:
- Dull, aching pain in the abdomen
- Mirena’s string becomes shorter or disappears
- Unexpected menstrual-type bleeding
More serious symptoms may be caused by a device that has perforated the uterine wall and is affecting other organs, has caused internal bleeding or has resulted in a severe infection.
- Nausea and vomiting
- Blood in the stool
- Bowel movement changes
- Difficulty breathing
- Sudden, severe lower abdominal pain
- Rapid heartbeat
- Dizziness or fainting
- Low blood pressure
- Severe or excessive vaginal bleeding
- Appearance of bruising in the abdominal area
The longer a device migration event is left untreated, the higher the risk for additional complications. However, symptoms of organ perforation are not always easily identified as they may mimic other conditions or go unreported.
Patients should be advised to report any changes that may be related to Mirena organ perforation. Any changes in consciousness, heart rhythm, or symptoms of excessive bleeding should be treated as an emergency.
How Is Organ Perforation Treated?
Patients who are asymptomatic may notice that the Mirena device’s string has become shorter or has “disappeared”. A physical exam will be followed by X-ray procedures to locate the device and plan for removal.
If device migration has caused perforation of the uterine wall, surgery will most likely be required to remove the device, assess the injury, and repair tissues if necessary. In some cases, surgery may be performed laparoscopically but severe cases will require a larger abdominal surgery.
Some patients have been required to undergo multiple surgeries to stop blood loss, remove the device and repair damaged tissues and organs. Depending on the patient’s specific condition, the patient’s fertility may be impacted as damage to the reproductive system may be permanent and prevent future pregnancies. Scar tissue development in the abdominal area may cause pain or other complications which may be debilitating.
What Is Pelvic Inflammatory Disease?
Mirena also increases the risk for pelvic inflammatory disease (PID), a severe bacterial infection that affects the uterus and other reproductive organs. The risk is highest during the first 20 days after placement and patients who have an existing vaginal infection at the time of Mirena placement are more likely to get PID.
Pelvic Inflammatory Disease (PID) is a bacterial infection that can result in damage to the female reproductive organs and may result in infertility if not treated. PID may also increase the risk of ectopic pregnancy, a life-threatening occurrence. Untreated PID can result in the growth of painful scar tissue which necessitates surgical treatment and, in some cases, requires a total hysterectomy to remove all reproductive organs. Many PID patients continue to have severe pelvic pain long after the infection is resolved. Women who have PID are more likely to have it again and should not use Mirena or any IUD.
What Are the Symptoms of Pelvic Inflammatory Disease?
Symptoms of pelvic inflammatory disease include:
- Nausea and vomiting
- High fever or chills
- Pain during urination
- Pain during intercourse
- Yellowish or greenish vaginal discharge
- Tenderness or dull pain in the stomach or abdomen
Symptoms of PID should be treated right away to minimize permanent damage.
Can You Still Get Pregnant with Mirena?
Mirena is reported to be effective at preventing pregnancy over 99% of the time. If pregnancy occurs, however, the presence of hormones may damage a developing fetus which may result in miscarriage and may cause the uterus to become infected or septic, resulting in a septic abortion, an extremely dangerous condition. If pregnancy is allowed to proceed, there is a high risk of premature birth. If a pregnancy occurs during Mirena use, it is recommended that the woman undergo surgical zygote removal.
Though pregnancy is rare with Mirena use, an estimated half of Mirena-related pregnancies are ectopic pregnancies. An ectopic pregnancy is often called “tubal” pregnancy as it often involves fertilized egg implantation in one of the fallopian tubes but may occur in the cervix or other areas outside of the uterus.
An ectopic pregnancy is generally considered a medical emergency and often requires surgical removal of the fallopian tube which can result in infertility. Women who have had a previous ectopic pregnancy are at higher risk and should not use Mirena.
What Is Spontaneous Abortion?
A spontaneous abortion is another name for a miscarriage. It occurs when a pregnant woman spontaneously loses a pregnancy before the 20th week of pregnancy. While miscarriages are natural and common, occurring in around 1 out of every 5 pregnancies, they can be painful, both emotionally and physically. If you get pregnant while using Mirena, the risk of miscarriage is higher than in women who were not using Mirena at the time they got pregnant.
What Is a Septic Abortion?
Spontaneous abortion occurs suddenly without precipitation but in some cases, not all of the endometrial tissue is shed from the uterus. Endometrial or fetal tissue that is left behind may become infected, and if not treated, can result in a life-threatening occurrence of sepsis. Pregnancy symptoms should be reported to a health care professional and symptoms of spontaneous abortion or symptoms of infection should be treated immediately.
What Is an Ectopic Pregnancy?
Mirena clinical studies indicate that the device has a pregnancy failure rate of 0.8% over a 5-year period and estimates show that half of these will be an ectopic pregnancy. In normal pregnancy, once the egg is fertilized, it travels to the uterus and attaches itself to the uterine wall. An ectopic pregnancy occurs when the fertilized egg attaches outside of the uterus. Most commonly, an ectopic pregnancy occurs in the fallopian tube and may be called a “tubal” pregnancy, but it may also occur in other areas like the cervix, ovaries, intestines or another abdominal organ.
Ectopic pregnancies are not considered viable and most often require surgical removal. If discovered early enough, surgical termination may be performed through laparoscopy, but emergency cases will usually require abdominal surgery.
If surgical removal is not performed, the dividing cells of the embryo will grow too large and may rupture the fallopian tube. This may result in severe hemorrhage which can be life-threatening. A patient who has had one ectopic pregnancy may be at increased risk for future ectopic pregnancy. Some patients experience early symptoms of ectopic pregnancy of abdominal pain, inflammation, and general pregnancy symptoms but others are asymptomatic until the tissue is ruptured.
What Are the Symptoms of an Ectopic Pregnancy?
Symptoms of ectopic pregnancy that may indicate rupture or hemorrhage include:
- Sudden, sharp abdominal pain
- Unexpected vaginal bleeding
- Dizziness or fainting
- Nausea and vomiting
- Pressure on rectum
- Low blood pressure
- Rapid heart rate
- Abdominal swelling
Any pregnancy symptoms that occur while using Mirena should be reported to a medical professional. Signs or symptoms of ruptured ectopic pregnancy or bleeding should be treated as a medical emergency.
What Happens If an Ectopic Pregnancy Isn’t Discovered?
If an ectopic pregnancy is not discovered quickly, the rapid cell division of the growing embryo may cause the fallopian tube to rupture. This may cause excessive internal bleeding or hemorrhage which can be life-threatening for the mother.
What Are the Symptoms of a Ruptured Ectopic Pregnancy?
Symptoms of ruptured ectopic pregnancy may include:
- Sudden and severe pain in the abdomen
- Swelling of abdomen
- Back, shoulder, or pelvic pain
- Pressure of rectum
- Dizziness or fainting
- Symptoms of low blood pressure
A hemorrhage associated with ruptured ectopic pregnancy may lead to life-threatening blood loss. symptoms of ruptured ectopic pregnancy should be treated as a medical emergency. In the western world, death due to ectopic pregnancy is rare but it may result in infertility as surgery is usually required to remove the affected fallopian tube and other involved tissues.
How Is a Ruptured Ectopic Pregnancy Treated?
A ruptured ectopic pregnancy is treated as a medical emergency due to the risk of life-threatening hemorrhage or blood loss. Surgery will be performed to control internal bleeding and may include removal of the fallopian tubes and other involved tissue, resulting in termination of the pregnancy.
If an ectopic pregnancy is discovered prior to rupture, removal of the device and termination of the pregnancy will be recommended. Termination may be performed through laparoscopy and medication known as methotrexate may be used to assist in the dissolution of the pregnancy. In some cases, removal of the fallopian tube may also be required even when a rupture has not occurred. This may have an impact on future fertility.
What FDA Warnings Are There Regarding Mirena?
Since 2004, the FDA has received over 47 thousand reports of adverse events related to Mirena use. In 2009, the FDA issued a warning to its manufacturer, Bayer for overstating the effectiveness of the device and minimizing risks. Bayer had claimed in its “Simple Style” live marketing talks targeting “busy moms” that the IUD would help women with increased libido and that they would “look and feel great”.
As shared in the warning letter, at least 5 percent of women using the Mirena IUD are reporting decreased libido during clinical trials. The Division of Drug Marketing, Advertising, and Communications (DDMAC), a department of the FDA that reviews marketing plans and documents of pharmaceuticals had concluded that this program overstated Mirena’s benefits while downplaying side effects.
Bayer has also been warned by the FDA regarding advertising for some of its other birth control products including Yasmin and Yaz oral contraceptives.
What Lawsuits Are There Against Bayer?
Thousands of women who were injured or developed severe side effects after receiving Mirena have filed lawsuits against the IUD’s manufacturer, Bayer Healthcare. The lawsuits have accused the company of marketing a dangerous medical product and claim that complications caused by the device and the drug it contains have resulted in serious injury. The lawsuits claim that Bayer is responsible for manufacturing a dangerous and defective device and did not adequately warn the medical community and the public about the risks of Mirena. The plaintiffs are seeking compensation for their injuries to cover medical costs, lost wages, pain, and suffering and in some cases, loss of future fertility.
Lawsuits have been filed in three major case groups including:
- Federal Mirena organ perforation lawsuits consolidated into multidistrict litigation (MDL 2434) in New York claim that IUD migration resulted in perforation of an internal organ such as the uterus or other abdominal organ. In 2016, 1,230 cases were dismissed however Bayer offered $12.2 million to settle the remaining cases in September 2018.
- Federal Mirena pseudotumor cerebri lawsuits consolidated into multidistrict litigation (MDL 2767) in New York claim that the hormone, levonorgestrel caused the formation of pseudotumor cerebri or “false brain tumor”. An estimated 1,000 cases were consolidated in this case however no settlements have been announced.
- New Jersey Mirena migration and injury lawsuits claim a variety of injuries and were consolidated in multicounty litigation (MCL 297). Some cases in this group were dismissed as the statute of limitations had expired but up to 1,800 additional cases may have been pending with no announced settlements.
What Device Migration Lawsuits Are There?
Miriam Cruz filed her Mirena lawsuit when the device she had implanted in 2008 caused her severe pain years after implementation. Bayer claimed that the only way Mirena would migrate would be if the doctor made a mistake during placement. However, since Cruz did not suffer until several years after placement, it is evident that the device did in fact migrate. In her Mirena lawsuit, Cruz claimed that the company did not properly inform her of such risks and that the product was not properly represented when she chose to use it.
Melody Williams filed a Mirena lawsuit claiming that Bayer Pharmaceuticals was guilty of fraud, negligent misrepresentation, and failure to warn patients of dangerous side effects. Williams started experiencing severe abdominal pain and cramping within a year of her implantation. Her device was found to have migrated through her right fallopian tube and required surgery to have it removed.
What Organ Perforation Lawsuits Are There?
Desaree Nicole Lee Johnson suffered permanent injuries after using a Mirena IUD which perforated her uterus. She required two surgeries to remove the device after the first was unsuccessful due to device migration into her abdominal cavity. After undergoing surgery, she became pregnant but had a miscarriage and was told that she may be infertile. Her complaint alleged that Bayer knowingly sold an unsafe and defective product, which led to her injuries.
Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA.
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