Depo-Provera Shots Triple Meningioma Brain Tumor Risks After Just One Year: Study

The findings of a new study have suggested that women receiving Depo-Provera birth control shots for more than one year face a 3.55 times greater risk of developing meningioma brain tumors when compared to those using certain oral contraceptives.

Depo-Provera is a hormonal birth control shot that was approved by the U.S. Food and Drug Administration (FDA) in 1992, which has been used by more than 70 million women, based on the belief that it is a safe and effective means of preventing pregnancy.

However, concerns over Depo-Provera brain tumor side effects first emerged in April 2024, after a study published in The BMJ revealed that Depo-Provera users may face a 5.5 fold increased risk of developing intracranial meningioma tumors, a condition that requires ongoing monitoring and in severe cases, surgical intervention.

As a result, dozens of women are now pursuing Depo-Provera lawsuits against the manufacturers, each raising similar allegations that false and misleading information has been provided about the potential side effects of the birth control shot. However, as more women learn that they may have developed a meningioma from Depo-Provera, the size and scope of the litigation is expected to continue to expand.

Annual Depo-Provera Injections Linked to 3x Meningioma Risk

Since the release of The BMJ study, there have been few efforts to quantify the actual risk of brain tumors in women who received regular Depo-Provera injections. However, this gap in research was recently addressed by a team from the University of British Columbia, who indicate that just a year of the quarterly Depo-Provera injections can triple the risk of meningiomas, marking one of the first efforts to specifically determine this risk.

In the new Depo-Provera study (PDF), Dr. Mahyar Etminan and a team of researchers compared brain tumor rates between Depo shot recipients and users of traditional birth control pills. The study involved more than 72,000 Depo-Provera recipients and 247,000 birth control pill users.

According to the findings, women who received the Depo-Provera shot for at least a year faced 3.55 times the risk of developing a meningioma than their oral contraceptive counterparts. They determined that for every 1,111 women receiving Depo shots, one would experience a meningioma.

The study points to actions taken by Pfizer in other countries, in which Pfizer updated the Depo-Provera special warnings and precautions for use label in the European Union (EU) and the United Kingdom to now list meningioma as a possible side effect. However, the manufacturer has failed to add Depo-Provera meningioma warnings to the label in the U.S.

“Recently, the European Medicines Agency has recommended the addition of meningioma as a warning in the drug’s label. However, to date, a label change has not taken place by the Food and Drug Administration,” Etminan’s team concluded. “Our study adds to the existing body of evidence that MPA can increase the risk of meningioma. We believe the results of this study further warrants the need to alert women about this serious, albeit rare adverse event.”

While the latest research supports the findings released in The BMJ’s last year, the study’s findings have not yet been peer-reviewed or published in a medical or scientific journal.

Depo-Provera Brain Tumor Lawsuits

As the number of Depo-Provera lawsuits in federal courts nationwide continues to grow, a group of plaintiffs filed a motion for transfer with the U.S. Judicial Panel on Multidistrict Litigation (JPML) in November 2024, asking the panel to centralize claims throughout the federal court system before one judge in the Northern District of California, for coordinated discovery and pretrial proceedings as part of a Depo-Provera MDL (multidistrict litigation).

According to the motion, each of the complaints raises common questions of fact and law, and thousands of lawsuits may ultimately be included in the litigation. Plaintiffs argue that the establishment of an MDL for the Depo-Provera lawsuits will help prevent duplicative discovery into common issues, avoid contradicting rulings, and serve the convenience of all parties, witnesses and the court system.

Following the motion, both Pfizer and manufacturers of generic versions of the birth control shot, also supported consolidation. However, they indicated it would be more appropriate to centralize the litigation in the Southern District of New York, close to Pfizer’s headquarters.

The parties presented their arguments to the JPML last week, and a decision is pending.

If the JPML agrees to consolidate the lawsuits into a Depo-Provera MDL, all current and future claims will be transferred to one judge for coordinated discovery, pretrial motions and potentially a series of early bellwether test cases.

However, if the parties fail to reach Depo-Provera brain tumor settlements or another resolution for the litigation after all pretrial proceedings are concluded, each individual lawsuit may later be remanded back to the U.S. District Court where it was initially filed for an individual trial in the future.