Danish Study of 3 Million Women Links Six Hormonal Birth Control Drugs to Meningioma Risk, Confirms Depo-Provera Has Strongest Association

A study published in JAMA Network Open has confirmed a link between the injectable contraceptive Depo-Provera and meningioma, a typically slow-growing brain tumor, while also identifying five additional hormonal birth control drugs carrying a similar, smaller risk.

Researchers at the Danish Medicines Agency reviewed 25 years of health records covering roughly 3 million women. Beyond Depo-Provera, they found small increases in meningioma risk tied to combined oral contraceptives and the mini-pill, specifically formulations containing desogestrel, drospirenone, gestodene, and levonorgestrel.

The Numbers, Precisely

Depo-Provera showed the strongest association, with roughly a 4-fold relative increase in risk. The combined pill and mini-pill showed a weaker link, around a 1.5-fold relative increase.

Relative risk numbers sound alarming in isolation, but the absolute risk tells a different story. About 5 women per 1,000 develop a meningioma over their lifetime. Among women using medroxyprogesterone, the injectable hormone in Depo-Provera, that number rises to roughly 6 per 1,000.

The study also found the elevated risk is not permanent. It persists only while a woman is using the drug and disappears within five years of stopping progestogen-based contraception.

What This Doesn't Mean

Cancer epidemiologist Paul Pharoah, who was not involved in the study, said in a press release that these small increases in risk need to be weighed against the real benefits contraception provides. Pharoah specifically warned women not to stop taking birth control pills without first consulting a doctor, given that unintended pregnancy carries its own well-documented health risks.

Meningioma is usually benign. But even benign tumors can cause serious problems by pressing on nerves or brain structures. The tumors affect women more than twice as often as men, likely tied to hormonal factors that can fuel their growth. When they turn malignant, meningiomas can trigger seizures and cognitive impairment, and are typically treated with surgery or radiation.

The Litigation Backdrop

Pfizer, which makes Depo-Provera, is currently facing hundreds of lawsuits alleging the company knew about the meningioma risk and failed to adequately warn patients. These are allegations made in active litigation. No court has issued a verdict establishing that Pfizer concealed known risks, and no regulatory finding of wrongdoing has been announced.

Elizabeth Fleurisma, one of 75 plaintiffs suing Pfizer in New York, told The New York Post she used Depo-Provera for nearly a decade and developed severe headaches, fatigue, and what she described as excruciating pain. She underwent a craniotomy, but surgeons could not remove the entire tumor, requiring multiple rounds of radiation therapy afterward. "When I came out of surgery, when I came home, it's almost like I didn't even know my environment," Fleurisma said.

The strongest case against these findings driving alarm is straightforward. Absolute risk increases of one extra case per 1,000 women are small by any clinical standard, and the risk is reversible after discontinuation. Public health officials and physicians will likely continue framing this as a manageable, disclosed tradeoff rather than a reason for mass discontinuation.

The strongest case for taking it seriously is also straightforward. Meningioma surgery and radiation are not minor interventions, as Fleurisma's case shows, and patients cannot weigh a risk they were never clearly told about. Whether Pfizer adequately disclosed that risk before this newer research is the exact question now sitting in front of courts handling the pending lawsuits.

Neither Pfizer's on-record legal defense nor a company statement addressing the JAMA Network Open findings specifically was available in the reporting reviewed for this story. The unresolved question is whether the hundreds of pending cases will produce a verdict, a settlement, or a dismissal, and whether the FDA will update contraceptive labeling in response to the six-drug findings rather than treating Depo-Provera as an isolated case.