The manufacturers of the Depo-Provera birth control shot have been accused of knowing about the link between their product and meningioma brain tumors for more than four decades, yet failing to warn women in the United States about this serious health risk. 

Lawsuits filed against Pfizer, the maker of Depo-Provera, allege that the pharmaceutical giant was aware of studies dating back to 1983 that established a connection between progesterone-based contraceptives and the development of brain tumors. Despite this knowledge, Pfizer continued to market and sell Depo-Provera without adequately informing patients or their doctors about the risk of cerebral meningioma. 

If you or a loved one used the Depo-Provera birth control shot for at least one year and were diagnosed with a meningioma brain tumor, you may be eligible to file a Depo-Provera lawsuit and receive compensation for your injuries. 

For more information about filing a Depo shot lawsuit or to start the process of filing your claim today, contact the law firm of Hissey Mulderig & Friend by calling our office toll-free at 1-866-806-8117, or send us a message using our free claims submission form on the right side of this page. 

Studies From 1983 Linked Progesterone to Meningioma Brain Tumors

Research establishing the link between progesterone and meningioma brain tumors has existed for decades, with some of the earliest studies published in 1983. 

According to court documents filed in the Depo-Provera litigation, scientists discovered in 1983 that meningioma tumor cells contain a high number of progesterone receptors. This finding was significant because it demonstrated that progesterone — the hormone found in Depo-Provera — could stimulate the growth and development of these brain tumors. 

A 1983 study published in the European Journal of Cancer found that progesterone receptors were present in meningioma cells, shattering the previous belief that brain tumors would primarily respond to estrogen. This research indicated that progesterone may play a critical role in how often meningiomas occur, how they behave, and how quickly they grow. 

Additional research published in 1984 built on these findings, further confirming that meningiomas contain high numbers of progestin receptors. Later studies found that antiprogesterone medications could help treat these tumors, providing even more evidence of the connection between progesterone exposure and meningioma development. 

Depo-Provera contains medroxyprogesterone acetate, a synthetic form of progesterone known as progestin. Given the scientific evidence available as early as 1983, plaintiffs argue that Pfizer had a duty to investigate the potential link between their product and brain tumors, a duty the company allegedly failed to fulfill. 

Lawsuits Allege Pfizer Failed to Warn Women About Depo-Provera Brain Tumor Risks

Despite the scientific evidence linking progesterone to meningioma, Pfizer failed to include warnings about brain tumor risks on Depo-Provera labels in the United States. 

Lawsuits filed by women diagnosed with meningioma brain tumors have alleged that Pfizer knew, or should have known, about the potential link between Depo-Provera and meningiomas as early as 1983, nearly a decade before the drug received FDA approval for use as a contraceptive in the United States in 1992. 

While regulatory agencies in other countries took action to warn women about the risk of brain tumors, the United States lagged behind. In 2022, both the European Medicines Agency and Health Canada required Pfizer to add meningioma warnings to Depo-Provera labels. South Africa’s drug regulatory agency also recommended updating the warning label in 2025. 

However, it was not until December 2025 that the U.S. Food and Drug Administration finally approved a label change for Depo-Provera that warned patients about the increased risk of meningioma brain tumors, more than 40 years after the initial scientific evidence emerged. 

Because of the decades-long delay between the first information about the link between the hormones in Depo-Provera and meningioma and the FDA warning, thousands of women may have unnecessarily been diagnosed with cerebral brain tumors.

Thousands of Women Diagnosed with Meningioma After Using Depo-Provera

As of February 2026, more than 2,000 women have filed Depo-Provera lawsuits against Pfizer after developing cerebral meningioma brain tumors following their use of the birth control shot. 

These lawsuits have been consolidated in a federal multidistrict litigation (MDL) in the United States District Court for the Northern District of Florida. The first Depo-Provera trial is scheduled to begin in December 2026, which could play a critical role in shaping potential settlement negotiations. 

Meningiomas are tumors that form in the tissue surrounding the brain and spinal cord. While most meningiomas are non-cancerous, they can cause serious complications depending on their size and location, including: 

• Severe headaches 
• Vision problems or vision loss 
• Seizures 
• Hearing loss 
• Memory problems and cognitive difficulties 
• Balance issues and dizziness 

Treatment for meningioma often requires invasive brain surgery, radiation therapy, or long-term medical monitoring. Many women who have undergone surgery to remove meningiomas face permanent disabilities, ongoing neurological problems, and significant medical expenses. 

Recent scientific studies have confirmed the link between Depo-Provera and meningioma. A 2024 study published in the British Medical Journal found that women who used Depo-Provera for more than one year were 5.5 times more likely to develop meningioma brain tumors compared to women who did not use the contraceptive. 

A separate study published in JAMA Neurology in 2025 found that Depo-Provera doubled the risk of developing meningioma, with the highest risk among women who started using the shot after age 31 or who had been treated with Depo-Provera for four years or more. 

Who Qualifies to File a Depo-Provera Meningioma Lawsuit?

Women who meet the following criteria may be eligible to file a Depo-Provera lawsuit and receive compensation: 

1. Used Depo-Provera, Depo-SubQ Provera 104, or authorized generic versions of the birth control shot; 
2. Received at least four injections (typically meaning one year or more of treatment); 
3. Were diagnosed with a cerebral meningioma brain tumor. 

Women who used the brand-name version of Depo-Provera before 2004 may have particularly strong claims, as Pfizer had decades to investigate the risks and provide adequate warnings but allegedly failed to do so. 

If you or a loved one developed a meningioma after using Depo-Provera, it is important to speak with a Depo-Provera attorney as soon as possible. Statutes of limitation vary by state and may limit the amount of time you have to file a claim after your diagnosis. 

Contact Hissey Mulderig & Friend to Start Your Depo-Provera Claim Today

The attorneys at Hissey Mulderig & Friend have more than 100 years of combined legal experience representing women who have been injured by defective drugs or medical devices, including birth control products like Depo-Provera. 

Our law firm is currently representing women nationwide who developed meningioma brain tumors after using the Depo shot. We understand the serious impact that a brain tumor diagnosis can have on you and your family, and we are committed to helping you pursue the compensation you deserve. 

Because our lawyers work on a contingency basis, you will not pay attorneys fees or costs unless we successfully recover damages in your case. We offer free, confidential case evaluations to help you understand your legal options. 

If you or a loved one used Depo-Provera and were diagnosed with cerebral meningioma – or if you have developed symptoms that may indicate a brain tumor – contact Hissey Mulderig & Friend today to start the process of filing your Depo-Provera lawsuit. 

You can reach our office toll-free at 1-866-806-8117, or send us a message using the free case evaluation form located at the top of this page.