Lawyers say Bayer should have warned women about the risk of developing brain injuries from Mirena, a contraceptive intrauterine device (IUD) that releases the hormone levonorgestrel.
In clinical trials, 16% of women on Mirena developed headaches or migraines — which are also the most common symptoms of Intracranial Hypertension (IH), or too much fluid inside the skull.
Other symptoms include neck pain, dizziness, nausea, ringing in the ears, double-vision, and progressive vision loss or blindness.
IH is also known as Pseudotumor Cerebri (PTC) because symptoms resemble a growing brain tumor. High pressure in the skull can also damage optic nerves, causing a condition called papilledema.
The first lawsuits linking Mirena and intracranial hypertension were filed in early 2014. That year, lawyers tried to consolidate the cases in Tennessee. Judges refused because there were only 9 lawsuits.
More than 100 lawsuits have been filed since August 2014. Lawyers say there now are enough cases to justify centralization and “many more” to come, according to a motion filed on December 29, 2016.
This time, lawyers requested the U.S. District Court for the Southern District of Mississippi, under Chief Judge Louis Guirola, Jr.
The proposed MDL would be separate from another one pending in the Southern District of New York (MDL No. 2434), involving injuries from migration of the Mirena IUD device causing uterine perforations.
In comparison, intracranial hypertension lawsuits claim the injuries are caused by levonorgestrel, a synthetic hormone that Mirena releases into the uterus to prevent pregnancy for up to 5 years.
In 1995, a study linking 56 cases of intracranial hypertension with Norplant was published in the New England Journal of Medicine. Norplant is another levonorgestrel-releasing IUD, like Mirena.
No one knows if levonorgestrel causes brain injuries, but headaches are very common. “Removal of the implants may help relieve this symptom,” the researchers concluded. Obesity and other medications can also contribute.
In 2015, another study of FDA side effect reports found higher rates of IH associated with Mirena. Bayer’s medical experts rejected the study as “erroneous and misleading.” The label on Mirena does not include warnings about IH or PTC.