The birth control device known as the Mirena IUS has been shown to cause a variety of dangerous side effects in women who use it, including migration of the intrauterine device (IUD) from its intended position in the vaginal canal. The U.S. Food and Drug Administration (FDA) issued warning letters in March and December 2009 accusing Bayer HealthCare Pharmaceuticals of overstating the benefits of its Mirena IUS contraceptive and downplaying its serious risks.

Bayer calls the Mirena IUS an “intrauterine system.” This is because it has multiple mechanisms of action. It can stop sperm from fertilizing an egg and stop a fertilized egg from implanting in the uterus. Otherwise, the device is the same T-shape and size of a standard IUD.

Among the most serious side effects linked to the Mirena IUS / IUD are perforation of the uterus, organ damage, internal bleeding and infertility.

The Wayward Mirena IUD

The Mirena IUS / IUD is inserted by a doctor and then slowly releases levonorgestrel (a synthetic version of the hormone progestin). This hormone thickens the cervical mucus, which prevents sperm from reaching an egg. The synthetic hormone also thins the lining of the uterus, which reduces the chances that a fertilized egg can implant itself and grow.

The Mirena IUS came onto the market in 2000.

Since then, women who have used it have reported adverse reactions that include:

• Severe pain
• Uterine bleeding
• Headaches
• Ovarian cysts

• Vaginitis (inflammation or infection of the vulva and vagina)
• Pelvic inflammatory disease.

Pelvic inflammatory disease (PID) is an infection of the uterus (womb), fallopian tubes (tubes that carry eggs from the ovaries to the uterus) and/or other reproductive organs. It causes symptoms such as lower abdominal pain. PID can lead to serious consequences, including infertility, ectopic pregnancy (a pregnancy in the fallopian tube or elsewhere outside of the womb), abscess formation and chronic pelvic pain.

A more serious problem with the Mirena IUS is that the device tends to move from where it is inserted. The migrating IUD can perforate the uterine wall, the intestines or other internal organs. It can also embed itself in the uterine wall or elsewhere in the abdominal cavity.