Many women who opt for Mirena as a contraceptive expect the benefits of the IUD to outweigh the detriments. However, many patients have reported headaches with Mirena and have since been diagnosed with a neurological condition known as pseudotumor cerebri.

Mirena is an intrauterine device, or IUD. It is implanted into the uterus by a physician and releases a small amount of a hormone, levonorgestrel, which prevents pregnancy.

It was approved for the prevention of pregnancy in 2000 and is more than 99 percent effective for up to five years.

Mirena thins the lining of the uterus, this decreasing menstrual flow and preventing pregnancy. The makers of Mirena do not exactly understand how this prevents pregnancy but they suspect it is successful because it may inhibit the survival of sperm, it may thicken the mucus in cervix so sperm cannot enter the uterus, or it may alter the wall of the uterus.

Regardless of how it works specifically, it is one of the most reliable forms of birth control available to women worldwide.

However, Mirena comes with some side effects. Many women have complained of headaches with Mirena and researchers have connected the use of this IUD with a condition known as pseudotumor cerebri.

Women who exhibit headaches with Mirena also may have an abnormal elevation of cerebrospinal fluid. Psuedotumor cerebri, also known as idiopathic intracranial hypertension, is a condition characterized by increased pressure around the brain.

This increased pressure often gives women headaches with Mirena. Idiopathic intracranial hypertension mimics the symptoms of a brain tumor, thus the name psuedotumor cerebri.

When cerebrospinal fluid builds up in the brain and cannot be reabsorbed by the bloodstream, pressure builds. This production of cerebrospinal fluid and its reabsorption is a constant cycle. This fluid is a cushion that protects the brain and spinal cord.

It is not exactly understood why increased levenorgestrel levels can inhibit the reabsorption of cerebrospinal fluid, but it is known that this is the probable cause of headaches with Mirena.

Other psuedotumor cerebri symptoms besides headaches with Mirena include nausea, dizziness, blurred or dimmed vision, ringing in the ears and seeing flashes of light.

A study done in the New England Journal of Medicine published in 1995 showed the connection between idiopathic intracranial hypertension and the use of levenorgestrel intrauterine devices.

The researchers looked at women who were in generally good health, were implanted with a levenorgestrel IUD, but also complained of severe headaches and problems with their vision.

Many women who have headaches with Mirena as well as other severe symptoms have filed lawsuits against the makers of the medical device, Bayer. Some plaintiffs claim that Bayer falsely represented the safety and efficacy of the Mirena IUD. The U.S. Food and Drug Administration has warned Bayer to take care about what they claim regarding Mirena and the truth of their claims.

If you or someone you love has experienced vision loss or severe headaches with Mirena, you may benefit from speaking to an experienced attorney to discuss your legal options.