A new Mirena study suggests that copper-based IUDs may have a similar rate of complications as Mirena IUDs, in contrast to other medical research studies, FDA reports, and a growing swarm of Mirena lawsuits.

The Mirena IUD is a type of birth control implant. It is designed to be implanted into the uterus by a physician, and remain in place for up to five years, blocking conception. Copper IUDs are similar devices, except that copper IUDs’ copper content kills sperm, while the Mirena IUD releases small amounts of hormones to prevent pregnancy.

While serious safety concerns have been raised regarding the Mirena IUD, a new study now contradicts some of these Mirena IUD side effects concerns.

Study Finds Mirena Complications Lower Than Other Research Suggests

A study called European Active Surveillance Study for Intrauterine Devices or EURAS-IUD reviewed data from 61,000 women from six countries, between 2006 and 2013. Their data was collected through written interviews with women and their physicians. When adjusted for the fact that Mirena has a larger market share than copper IUDs, their research showed that the Mirena IUD and copper IUDs had a similar and relatively low rate of complications. This finding is in contrast to serious concerns about the safety of the Mirena IUD seen in other studies.

FDA Data Reports Frequent Mirena IUD Complications

Despite this recent study, here in the United States, the FDA’s data suggests a more dire situation regarding Mirena. In fact, during a 13-year span between 2000 and 2013, the FDA received 70,000 adverse reports from Mirena IUD users. Not all of these reported complications were uterine perforations, but a report from radiologists at the University of California held that uterine perforation was a “frequent” complication from the Mirena IUD.

Mirena IUD Lawsuits

Additionally, there have been hundreds of Mirena lawsuits filed by women who suffered from uterine perforation in the United States. These Mirena lawsuits commonly allege that drug manufacturing giant Bayer, the makers of the Mirena IUD, were aware—or reasonably should have been aware—of the serious risk of uterine perforation associated with the Mirena IUD. Mirena lawsuits often seek to recoup the cost of medical care allegedly linked to uterine perforation and other Mirena side effects, including emergency surgery to remove the IUD.

So many Mirena IUD lawsuits have been filed that the court system has had to resort to a type of group litigation called a multidistrict litigation or MDL. In MDLs, the court groups similar cases together. The Mirena IUD lawsuits are ideal for inclusion in a Mirena MDL, since they make similar accusations against Bayer and hinge on similar evidence. The Mirena MDL is designed to help streamline the legal process by grouping these similar Mirena lawsuits together.

The Mirena MDL is In Re: Mirena IUD Products Liability Litigation, MDL No. 2434, in the U.S. District Court for the Southern District of New York.