For more than three decades, the Depo-Provera birth control shot has been one of the most widely prescribed contraceptives in the United States. However, a growing body of research has raised concerns about a potential link between the Depo shot and meningioma, a form of tumors that can develop in the tissue surrounding the brain and spinal cord. 

Approved by the FDA in 1992, the Depo shot contains the active ingredient medroxyprogesterone acetate (MPA), a synthetic form of the hormone progesterone known as a progestin. Administered as an injection every three months, Depo-Provera was marketed to women as a convenient, effective, and low-maintenance form of birth control.  

For women who relied on the Depo shot for years without being told about the potential risk of developing brain tumors, these scientific findings have prompted urgent questions about what the drug’s manufacturer knew, when it knew it, and why warnings were not provided sooner. 

What Is a Meningioma?

Meningiomas are the most common type of primary brain tumor, accounting for roughly one-third of all brain tumors diagnosed in the United States. They are typically classified as benign, meaning they are not cancerous.  

However, that classification can be misleading. Because meningiomas develop inside the skull, even slow-growing tumors can press against brain tissue and cause significant neurological complications. 

Common symptoms of meningioma include:  

• Persistent headaches 
• Blurred or double vision 
• Hearing loss 
• Memory difficulties 
• Seizures 
• Weakness or numbness in the arms or legs.  

Depending on the size and location of the tumor, some patients require surgical removal, radiation therapy, or ongoing monitoring through imaging.  

Recovery from brain surgery carries its own set of risks, and some women have required multiple operations to address recurring or incompletely removed tumors. 

The Role of Progesterone Receptors in Brain Tumors

Understanding why Depo-Provera may be linked to meningioma requires a closer look at how hormonal exposure can influence brain tumor growth.  

Research dating back to the early 1980s established that meningioma cells frequently contain progesterone receptors. A 1983 study published in the European Journal of Cancer confirmed the presence of progesterone receptors in meningioma tissue, a discovery that challenged earlier assumptions that brain tumors responded primarily to estrogen. 

Subsequent research reinforced this finding. Studies have reported that anywhere from 33% to 89% of meningiomas express progesterone receptors on their cell surfaces. This means these tumors may respond directly to progesterone exposure, and that synthetic progestins like MPA, the active ingredient in Depo-Provera, could potentially stimulate tumor cell growth when they bind to those receptors. 

This hormonal connection is consistent with well-documented clinical observations. Meningiomas are diagnosed in women at rates significantly higher than in men, with some studies showing a 3-to-1 ratio among adults of childbearing age. Meningiomas have also been observed to grow more rapidly during pregnancy, a period marked by elevated progesterone levels.  

These patterns suggest that hormonal exposure plays a meaningful role in the development and progression of these tumors. Lawsuits filed against Pfizer allege that evidence of this connection was available as early as 1983, nearly a decade before the drug received FDA approval for contraceptive use. 

The 2024 BMJ Study: MPA Linked to Brain Tumor Surgery

The study that brought the Depo-Provera and meningioma link into sharp public focus was published in March 2024 in the British Medical Journal (BMJ). Conducted by researchers at France’s National Agency for Medicines and Health Products Safety, the study analyzed health records from more than 18,000 women who underwent surgery for intracranial meningiomas between 2009 and 2018. 

The researchers examined the contraceptive histories of these patients and found a significant association between prolonged use of injectable medroxyprogesterone acetate and the likelihood of meningioma requiring surgery.  

The study found that the association was concentrated among women who had used the injection for one year or longer, while shorter durations of use did not show the same pattern. Notably, no cancerous meningiomas were identified among the patients who had used Depo-Provera, and approximately two-thirds of users with meningiomas were over the age of 45. 

The study’s significance was amplified by the fact that Depo-Provera is far more widely used in the United States than in Europe, making the potential public health implications for American women considerably larger. 

The 2025 JAMA Neurology Study on Depo-Provera

In September 2025, a team of researchers from the Cleveland Clinic and Case Western Reserve University published findings in JAMA Neurology that provided the first large-scale U.S. data on the connection between Depo-Provera and meningioma. The study drew from the TriNetX database, a national network of 68 healthcare organizations, and analyzed records spanning from December 2004 to December 2024. 

The study compared meningioma incidence among women who used Depo-Provera against those who used other forms of hormonal contraception, including oral contraceptives, intrauterine devices, and subdermal implants, as well as women who used no hormonal contraception at all.  

The results showed a meaningful association between Depo-Provera use and subsequent meningioma diagnosis. The association was stronger among women who used the drug for more than four years and among those who began using it after age 31. Research into whether longer Depo-Provera use increases meningioma risk has become a focal point of both the medical literature and the ongoing litigation. 

The JAMA Neurology findings are particularly important because the study’s large sample size and U.S.-based data addressed some of the limitations identified in the earlier French research. The consistency of findings across two independent studies conducted in different countries using different methodologies strengthened the overall body of evidence. 

FDA Responds With Warning Label Update

In December 2025, the U.S. Food and Drug Administration approved a label change for Depo-Provera that, for the first time, included a warning about meningioma. The updated prescribing information instructs healthcare providers to monitor patients for signs and symptoms of meningioma and to discontinue the drug if a meningioma is diagnosed. 

This label change came more than 33 years after Depo-Provera’s initial FDA approval and roughly two years after the BMJ study was published. It also came well after regulatory agencies in Canada, the United Kingdom, and the European Union had already added meningioma warnings to Depo-Provera packaging in their respective markets.  

The timing of the U.S. warning is now a central issue in the Depo-Provera litigation, with thousands of women filing lawsuits alleging that Pfizer knew or should have known about the meningioma risk far earlier and should have sought label changes sooner.  

These cases were recently consolidated into a federal multidistrict litigation (MDL) in the Northern District of Florida, with bellwether trials expected to begin in late 2026. 

What This Means for Women Who Used Depo-Provera

For the millions of women who received Depo-Provera injections over the past three decades, this new information about the risk of developing cerebral meningioma after using the birth control shot represents a significant development.  

Women who used the Depo shot for a year or more and were later diagnosed with a meningioma may not have been given the information they needed to make a fully informed decision about their birth control options. Depo-Provera users may also have questions about what medical records they need to file a claim and whether they meet the eligibility criteria for a lawsuit.  

The attorneys at Hissey Mulderig & Friend can help answer those questions and guide you through the process of taking legal action. Our law firm has represented women across the U.S. in lawsuits involving birth control products, including the Ortho Evra patch, Yaz and Yasmin birth control pills, and the Paragard copper IUD. 

If you or a loved one used Depo-Provera and were diagnosed with a meningioma brain tumor, or if you are experiencing symptoms such as persistent headaches, vision changes, numbness, or seizures, you may be eligible to file a lawsuit and receive compensation.  

Contact the lawyers at Hissey Mulderig & Friend to find out more or start your claim by calling our office toll-free at 1-866-806-8117. You can also submit your information online using our free Depo-Provera case evaluation form, located at the top of this page.