Mirena is an IUD, or intrauterine device, made by Bayer. It is a type of contraceptive that is inserted into the uterus and used for up to five years to prevent pregnancy. On the market since it was approved by the U.S. Food and Drug Administration in 2000, Mirena has proven to be popular and it has been heavily marketed by Bayer as a simple, safe, and effective alternative to other types of birth control.

These claims have not been true for all women, though. Many have suffered complications and side effects from Mirena that range from mild to severe. Lawsuits are being filed against Bayer by these women who have suffered and who claim that Bayer did not warn them of the potential risks of using the device and marketed something they knew to come with serious risks and potential complications.

What is Mirena?

Mirena is an intrauterine device, a small medical device that is inserted into the uterus to prevent pregnancy. It is an alternative to more permanent birth control procedures like tubal ligation and the more temporary oral contraceptives. Mirena is inserted and is indicated to prevent pregnancy for up to five years. At that point, the device is supposed to be removed and can be replaced with another.

Mirena is supposed to give women the option of having long-term birth control without the need to take a daily pill, while at the same time being reversible. The device need only be removed and a woman can again become pregnant. The fact that there is not a daily pill to remember makes Mirena more effective than oral contraceptives.

Uses for Mirena

The FDA approved Mirena for contraceptive uses for up to five years, especially for women who have already had one child. There are several contraindications for the device. It should not be used in a woman who may be pregnant, who has uterine fibroids, who has or has had pelvic inflammatory disease, who had had abnormal bleeding or who has had an abnormal pap smear. It should also be avoided in women who have had endometriosis after giving birth, who have certain infections, or who may have breast cancer or liver damage, or who may be allergic to any materials in the device.

Although Mirena is indicated for preventing pregnancy, doctors may also prescribe it to treat heavy menstrual periods, endometriosis, anemia, chronic pelvic pain, or severe menstrual cramps. It may even be effective in preventing the need for a hysterectomy, the removal of the uterus.

How it Works

Bayer’s Mirena was approved by the FDA in 2000. It was not the first IUD contraceptive to be invented. Those made from copper were used in the 1960s and 1970s. Mirena was, however, the first IUD contraceptive to use hormones to prevent pregnancy. The device works by releasing a small amount of levonorgestrel, a synthetic form of the hormone progesterone, every day.

The hormone prevents fertilization of an egg by sperm in several ways: It causes the mucus of the cervix to thicken. It alters the wall of the uterus. It also inhibits the ability of sperm to survive in the uterus. Unlike other types of hormonal contraception, the Mirena device does not stop ovulation; it only stops the fertilization of the released egg.

Side Effects

There are several possible side effects that women using Mirena may experience. The most common adverse events include headaches, acne, irregular bleeding, tenderness in the breasts, cramping, pelvic pain, ovarian cysts, weight gain, mood swings, and amenorrhea. This last side effect is the absence of menstrual periods and it is most often seen after one year of use of the device.

Expulsion of the device is also possible. This occurs when the device comes out on its own. This is not dangerous, but pregnancy is possible until it is reinserted.

Although not common, a serious infection, called pelvic inflammatory disease, or PID, in the days or weeks following the insertion of Mirena is possible. This can become life-threatening if not treated right away. A sign of an infection is severe pain in the abdomen. If not treated immediately, this infection can lead to infertility and damage to internal organs.

Embedment

Most of the side effects of Mirena are not serious, but there are some possible complications that can become severe and require further medical attention. Embedment may occur, which happens when the device adheres to the wall of the uterus. In this position Mirena may not be effective at preventing pregnancy and it may require surgery to have it removed.

Migration and Perforation

Another potentially serious consequence of having an IUD implanted is the migration of the device. This happens when the device detaches from the uterus and migrates to another position. This can lead to the device puncturing or perforating the uterus or cervix. Perforation is not always detected right away, and can lead to unwanted pregnancies.

When perforation is not detected or treated it can also lead to the device migrating outside of the uterus. This can cause it to adhere to other organs. It can lead to perforation of the intestines, obstruction of the intestines, infections, abscesses, and other serious complications, which may require surgery to treat.

Ectopic Pregnancy and Other Complications

While Mirena is largely effective at preventing pregnancy, complications like embedment or perforation can reduce that effectiveness and lead to pregnancies. Half of the pregnancies seen in women with Mirena are ectopic, which means the egg is fertilized and implants in the fallopian tubes instead of in the uterus. This is life-threatening and requires surgery to remove the fertilized egg.

When pregnancy occurs with Mirena and is not ectopic, there are still serious potential complications. It is recommended that the device be removed immediately if a woman becomes pregnant. If it is not the woman may experience a septic abortion, a condition in which the uterus becomes infected. This is life-threatening. Pregnancy with the device in place can also lead to premature delivery or miscarriage.

Lawsuits

Many women who have suffered some of these serious complications have filed lawsuits against Bayer, the maker of Mirena. They claim that the company did not adequately warn patients or doctors of the potential risks and that it misrepresented the safety of the device. This claim may have merit, according to the FDA. In 2009 the agency issued a warning letter to Bayer that their advertising for Mirena made misleading claims about the potential benefits. Bayer is denying allegations, and no settlements have been made yet.