Health Risks of Depo-Provera and the Ongoing Lawsuit

What Is Depo-Provera?

Depo-Provera is an injectable birth control shot made by Pfizer. It contains medroxyprogesterone acetate (MPA), a synthetic form of the hormone progesterone. Women receive the injection every 12 weeks, in the upper arm or buttocks. The FDA approved Depo-Provera as a contraceptive in 1992, and it has since been used by tens of millions of women in the United States and around the world.

According to the Centers for Disease Control and Prevention (CDC), roughly one in four sexually active women in the U.S. has used Depo-Provera at some point. Black women use it at nearly double the national average.

The drug works by preventing ovulation. It also thickens cervical mucus and thins the uterine lining to reduce the chance of pregnancy. When used as directed, Depo-Provera is more than 99% effective at preventing pregnancy. For many women, it also reduces or eliminates monthly periods, which some find convenient. However, new research and updated federal warnings have raised serious concerns about risks tied to long-term use.

The Meningioma Risk: What Studies Show

A meningioma is a tumor that forms on the membranes surrounding the brain and spinal cord. Most meningiomas are not cancerous, but they can still be dangerous. As they grow, they press against brain tissue and can cause headaches, vision changes, hearing loss, seizures, and other serious neurological problems. About 39,000 meningiomas are diagnosed in the U.S. each year.

Research has found a significant link between prolonged use of injectable MPA (the active ingredient in Depo-Provera) and the development of meningioma. A landmark 2024 study published in The BMJ found that women who used injectable medroxyprogesterone acetate for one year or more had approximately 5.6 times the odds of being diagnosed with a surgically treated intracranial meningioma compared to non-users.

A large U.S. study published in JAMA Ophthalmology / PubMed (2025), which reviewed data from over 61 million female patient records, found that women using depot medroxyprogesterone acetate had a relative risk of 2.43 for meningioma diagnosis compared to controls. The risk was especially pronounced in women with more than four years of exposure, or in women who started use after age 31.

A separate review published in Frontiers in Global Women’s Health (2025) confirmed these findings, showing a dose-dependent effect: the longer a woman used Depo-Provera, the higher her risk of developing meningioma. Women who used the drug for 10 to 15 years had odds ratios above 2.3; women with more than 15 years of use had even higher risk.

Notably, Canada and the European Union had already added meningioma warnings to Depo-Provera labels by 2022 to 2024, years before the U.S. did the same.

Other Documented Health Risks

Meningioma is not the only health concern linked to Depo-Provera. The drug carries a FDA “black box” warning (the most serious type of warning the agency can require) for loss of bone mineral density.

• Bone density loss (osteoporosis risk): Depo-Provera lowers estrogen levels, which can lead to significant loss of bone mineral density. The FDA’s prescribing label warns that this bone loss is greater the longer the drug is used and may not be completely reversible after stopping. The agency recommends that Depo-Provera not be used for more than two years unless no other adequate birth control method exists. Young women and teenagers who use the drug during a critical bone-building window face particular concern.
• Weight gain: According to the Cleveland Clinic, weight gain is one of the most commonly reported side effects. Studies show users gained an average of about five pounds in the first year of use, though this varies.
• Irregular or absent periods: Changes in menstrual bleeding are the most common side effect. After one year of use, about 55% of users stop getting their periods altogether. While this is not medically dangerous for most women, it can be unsettling.
• Delayed return to fertility: After stopping Depo-Provera, it can take 10 months or more before ovulation resumes. For some women, it takes longer. Research published in PLOS ONE found that women who used Depo-Provera were nearly five times more likely to experience a fertility delay upon stopping compared to users of other contraceptive methods.
• Other reported effects: Depression, headaches, dizziness, decreased sex drive, bloating, and mood changes have all been reported by Depo-Provera users, according to the Mayo Clinic.

The Ongoing Lawsuit: Who Is Suing and Why

Thousands of women across the United States have filed lawsuits against Pfizer over Depo-Provera. The central allegation in most cases: Pfizer knew, or should have known, about the connection between Depo-Provera and meningioma brain tumors, and failed to warn patients and doctors in the U.S.

Lawsuits allege that Pfizer had access to research dating back to the 1980s showing a possible link between progesterone-based drugs and meningioma development, according to litigation records reported by legal observers. In late 2023, Pfizer itself concluded internally that a potential causal link existed between long-term MPA use and meningioma. The company submitted a request to the FDA in February 2024 to add a warning to the label, a request that was initially denied. Pfizer resubmitted in June 2025, and the FDA approved the warning in December 2025.

In the meantime, plaintiffs argue that Pfizer provided stronger meningioma warnings on Depo-Provera labels in other countries (including Canada and EU member states) while U.S. women remained uninformed.

In February 2025, the U.S. Judicial Panel on Multidistrict Litigation (JPML) consolidated the federal cases into a Multidistrict Litigation (MDL) assigned to Judge M. Casey Rodgers in the Northern District of Florida. As of March 2026, more than 3,000 cases are pending in the MDL. The first bellwether trial is scheduled for December 2026.

Pfizer has sought to dismiss many of the claims using a legal defense called “federal preemption,” arguing that it cannot be held liable under state law because the FDA had initially rejected its label change request. That argument became significantly weaker after the FDA approved the meningioma warning in December 2025. The court is currently evaluating witness testimony on general causation, with key briefing deadlines running through spring 2026.

These lawsuits are not a class action. Each case is handled individually within the MDL, which means each plaintiff’s damages are evaluated based on her specific injuries and circumstances.

Who May Be Affected

Women who used Depo-Provera for an extended period and later developed a meningioma may have a potential claim in the ongoing litigation. Based on current MDL eligibility criteria reported by Drugwatch, the following general criteria are being considered:

• Used Depo-Provera, Depo-subQ Provera 104, or an authorized generic for at least 12 months
• Were diagnosed with an intracranial meningioma after starting Depo-Provera injections
• Have medical records documenting both Depo-Provera use and the meningioma diagnosis

The medical research published in Frontiers in Pharmacology indicates that the risk is strongest with longer durations of use and does not appear to be linked to oral forms of medroxyprogesterone. Only the injectable version shows this elevated risk.

Each state has its own deadline for filing a personal injury lawsuit (called a statute of limitations). If you believe you or a family member may have been affected by Depo-Provera, speaking with an attorney as soon as possible is important so that deadlines are not missed.

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