The difference is real but small.
For generations, hormonal contraception has quietly reshaped the arc of women's lives — offering autonomy, relief, and possibility. Now, a sweeping Danish study drawing on 25 years of health records has surfaced a rare but measurable association between certain contraceptives, particularly injectable progestogens, and meningioma, a mostly benign brain tumor. The absolute risk remains small and appears to recede after discontinuation, yet the finding invites a deeper reckoning with how medicine weighs the freedoms it grants against the harms it may quietly carry.
- A Danish study of three million women — the most precise of its kind — confirms that injectable contraceptives like Depo-Provera carry a roughly fourfold relative increase in meningioma risk, a finding regulators can no longer set aside.
- Though the absolute numbers are modest — rising from five to six cases per thousand women — thousands of patients who developed tumors have already filed lawsuits against Pfizer, and some have endured seizures and lasting cognitive harm.
- The FDA moved in December 2025 to require updated warning labels on Depo-Provera, while the European Medicines Agency has opened its own investigation, signaling that institutional accountability is catching up to the science.
- Crucially, the elevated risk appears reversible — fading within five years of stopping the contraceptive — and meningiomas remain 90 percent benign and highly treatable, tempering alarm without dismissing it.
- Experts are urging not abandonment of hormonal contraception but a shift toward genuinely informed consent, reminding patients and prescribers alike that pregnancy itself carries mortality risk, and that the goal is choice made with clear eyes.
For decades, hormonal birth control has given millions of women the power to shape their own reproductive lives. But a landmark Danish study — drawing on 25 years of health records from roughly three million women — has now produced the clearest evidence yet that certain contraceptives are linked to meningioma, a tumor that forms in the membrane surrounding the brain.
The findings vary by contraceptive type. Injectable medroxyprogesterone, sold as Depo-Provera, showed the strongest association — a roughly fourfold increase in relative risk. Combined oral contraceptives and mini-pills showed a more modest 1.5-fold increase. In absolute terms, the difference is small: lifetime meningioma risk rises from about five to six cases per thousand women using Depo-Provera. And the elevated risk appears to fade within five years of stopping the contraceptive.
Meningiomas are typically benign — around 90 percent — and survival rates are high. But they are not without consequence. Some cause seizures and cognitive difficulties, and the diagnosis carries real weight. Since 2024, thousands of women have filed lawsuits against Pfizer. In December 2025, the FDA approved updated warning labels acknowledging the possible link, and the European Medicines Agency has opened its own investigation.
The biology offers a plausible explanation: meningiomas carry progesterone receptors, tumors tend to accelerate during pregnancy, and women develop them at more than twice the rate of men. Synthetic progestogens used in contraception may stimulate the same pathways.
Experts are careful not to frame this as a reason to abandon hormonal contraception. Pregnancy itself carries mortality risk, and progestogens treat a range of serious conditions. The call from clinicians is not for alarm but for honesty — thorough conversations between prescribers and patients so that whatever choice is made is genuinely informed.
For decades, hormonal birth control has given millions of women the ability to plan their lives—to space pregnancies, manage painful periods, and chart their own reproductive futures. But a large study from Denmark has now raised a question that doctors and patients can no longer ignore: does the hormone in some contraceptives slightly increase the risk of a rare brain tumor?
Researchers at the Danish Medicines Agency spent years sifting through 25 years of health records covering roughly three million women. What they found, published in JAMA Network Open, is the clearest evidence yet that certain types of hormonal contraception are indeed linked to meningioma, a tumor that grows in the membrane surrounding the brain. The connection had been suspected for years, but earlier studies produced mixed results, often because they failed to distinguish between women currently using contraception and those who had stopped. This new analysis was more precise.
The findings break down by contraceptive type. Injectable birth control—specifically medroxyprogesterone, sold under the brand name Depo-Provera—showed the strongest association, with a roughly fourfold increase in relative risk. Combined oral contraceptives and mini-pills showed weaker associations, with about a 1.5-fold increase. These numbers sound alarming until you look at the absolute risk. About five women per thousand will develop a meningioma in their lifetime. For women using Depo-Provera between ages 25 and 44, that number rises to six per thousand. The difference is real but small. And crucially, the elevated risk appears to fade within five years of stopping the contraceptive.
Meningiomas are rare, and when they do occur, roughly 90 percent are benign. But they are not harmless. Some cause seizures and cognitive problems. They are typically treated with surgery or radiation therapy, and survival rates are high—over 90 percent in Australia, for instance. Still, the diagnosis carries weight. Since 2024, thousands of women who developed meningiomas after receiving Depo-Provera injections have filed lawsuits against Pfizer. In December 2025, the FDA approved a new warning label for the injection acknowledging the possible connection.
The biological mechanism is plausible. Meningiomas have receptors that respond to progesterone, the natural hormone that regulates the menstrual cycle and pregnancy. Progestogens—synthetic compounds that mimic progesterone—are used in several types of contraception. Women are more than twice as likely as men to develop meningiomas, and the tumors tend to grow faster during pregnancy or when patients take progesterone-like drugs. It is reasonable to suspect that hormones play a role.
But experts stress that the picture is more complicated than a simple risk-benefit calculation. An obstetrician from the University of Queensland points out that pregnancy itself carries risks: a maternal mortality rate of 6.6 per hundred thousand in Australia. Unintended pregnancy carries its own health consequences. A gynecologist not involved in the study notes that progestogens are effective treatments for debilitating conditions and suit many women who need contraception. The question is not whether to use hormonal birth control, but how to make an informed choice.
A reproductive endocrinologist from Imperial College London emphasizes that the study did not examine hormone replacement therapy, which uses much lower doses of progesterone and is not expected to increase meningioma risk. The findings apply specifically to contraceptive doses. An investigation into the association is now underway at the European Medicines Agency. Experts agree that prescribers should be aware of the link and that women deserve thorough conversations about the risks and benefits of different contraceptive options before a prescription is written. The goal is not to scare women away from contraception, but to ensure that the choice, when made, is truly theirs.
Notable Quotes
These very small increases in risk need to be balanced against the benefits of different forms of contraception. It is important that women do not stop using their birth control pills without consulting their doctor.— Paul Pharoah, cancer epidemiologist, Cedars-Sinai Health Sciences University
Prescribers should certainly be aware of the association. This is further evidence of the importance of appropriate contraceptive consultations addressing risks and benefits of various means of contraception.— Gino Pecoraro, obstetrician and gynecologist, University of Queensland
The Hearth Conversation Another angle on the story
So the study found that Depo-Provera increases meningioma risk fourfold. That sounds serious. Should women stop using it?
The fourfold number is relative risk—it sounds bigger than it is. The absolute increase is from five cases per thousand women to six. That's one additional case per thousand. It matters, but it's small.
And the risk goes away when you stop taking it?
Yes. Within five years of stopping, the elevated risk generally disappears. That's actually important—it suggests the hormone itself is driving the association, not something permanent.
Why did earlier studies miss this?
They often didn't separate current users from past users. If you lump everyone together, the signal gets muddied. This study was more careful about that distinction.
What about the women who've already developed tumors and sued Pfizer?
Their experience is real and serious. Some had seizures, cognitive problems. The lawsuits pushed the FDA to add a warning label. But the study suggests that if they'd stopped the injection earlier, the risk would have declined.
So what should a woman do if she's on Depo-Provera?
Talk to her doctor. Don't stop on your own. The benefits of contraception—preventing unintended pregnancy, managing painful periods—have their own health weight. The conversation should be informed, not panicked.