Injectable Birth Control Linked to Higher Risk of Brain Tumors
Description
STORY AT-A-GLANCE
Long-term use of injectable birth control like Depo-Provera is linked to a significantly higher risk of brain tumors, especially meningiomas
Women who started injections after age 30 faced dramatically higher risks, with increases ranging from 175% to 277% depending on age group
A French study found women using injectable birth control for more than a year were over five times more likely to need brain tumor surgery
Unlike synthetic hormone shots, options such as barrier methods and fertility awareness carry no increased risk of brain tumors
Natural progesterone supports your body’s balance by countering excess estrogen, calming your nervous system, and protecting long-term brain health
A growing number of women are learning that their contraceptive choice carries hidden risks. Injectable birth control, promoted for decades as safe and convenient, is now being tied to serious brain tumors. What makes this issue even more urgent is that millions of women have relied on these shots worldwide, often unaware of the dangers.
Stories from patients and mounting evidence from international research are sounding the alarm. Women who trusted that their birth control protected their health are instead facing devastating diagnoses, life-altering surgeries, and long-term neurological complications. At the same time, health authorities in countries like Canada and those in the European Union have already issued warnings, while women in the U.S. remain largely uninformed.
This gap in awareness raises a key question: how long have these risks been known, and why are American women still left in the dark? The answers begin to emerge when looking at the most recent research linking injectable synthetic hormones to brain tumor growth.
Hormone Shots and Brain Tumor Risk Uncovered
Research published in JAMA Neurology investigated whether depot medroxyprogesterone acetate (DMPA), a common injectable contraceptive widely known by the brand name Depo-Provera, influences the risk of developing meningioma, a tumor that grows in the protective layers of the brain and spinal cord.1 The study analyzed millions of electronic health records from 68 health care organizations across the U.S.
Findings show a sharp rise in risk with long-term use — According to the data, women who used DMPA had more than twice the risk of developing meningioma compared with women who did not use this contraceptive. The study emphasized that duration of use mattered greatly. Those with more than four years of exposure had significantly higher risks compared to short-term users.
Age at first use shaped outcomes dramatically — Women who began injections between ages 31 and 40 faced a 277% higher risk of meningioma compared to non-users, those starting at 41 to 50 had a 175% higher risk, and women who initiated after 50 saw a 220% increase.2 These findings show that the timing of exposure plays a role alongside duration of use.
Other contraceptive methods showed striking differences — Oral forms of medroxyprogesterone acetate carried only a smaller increase in risk, while contraceptives like intrauterine devices (IUDs) and implants did not show any link to higher tumor rates.
Hormone sensitivity of tumors — Meningiomas often express progesterone receptors, meaning they respond strongly to progesterone or synthetic forms of it like medroxyprogesterone acetate.3 This suggests that repeated hormone exposure could fuel tumor growth in susceptible women. By binding to progesterone receptors on meningioma cells, synthetic hormones act as a signal to grow and multiply.
The findings help you personalize decisions — If you're in your early 30s or planning to use contraception for many years, the findings provide strong evidence that injectable medroxyprogesterone carries added risk. Understanding how these risks differ based on age and duration of use empowers you to make safer, more informed health choices.
French Study Uncovers Striking Rise in Brain Tumor Risk from Hormone Shots
A national case-control study published in The BMJ examined whether long-term use of certain synthetic hormones, known as progestogens, increased the risk of requiring surgery for meningioma.4 Researchers analyzed medical records from data in the French National Health Data System, giving them access to one of the largest databases of hormone use and surgical outcomes.
The analysis compared 18,061 women who underwent surgery for meningioma with 90,305 control patients who did not have tumors. This large population allowed the researchers to identify patterns that would not be visible in smaller studies, particularly regarding long-term hormone use.
Injectable medroxyprogesterone showed the highest risk increase among contraceptives — Women who used injectable medroxyprogesterone acetate for more than a year had more than five times the risk of undergoing meningioma surgery compared to women who never used it.
Other hormones carried different levels of risk — Unlike the injectable form, natural progesterone, dydrogesterone, and levonorgestrel-releasing IUDs showed no link to meningioma surgery. This difference highlights that not all hormones are equal when it comes to brain tumor risk. The type of progestogen, its dose, and the delivery method all played a role.
Duration of use was a key driver of harm — Short-term use did not trigger the same level of concern, but long-term exposure — especially over 12 months — caused a dramatic increase in surgical cases. The findings emphasize that the body responds differently to prolonged hormone exposure, which is critical for you to consider if you're weighing contraceptive options for years rather than months.
Contraceptives and Glioma Risk in Younger Women
Research published in the British Journal of Clinical Pharmacology examined the link between hormonal contraceptive use and glioma, a type of brain cancer that develops in the supportive cells of the brain.5 Unlike meningiomas, which are often benign, gliomas are aggressive and frequently life-threatening, making the findings especially important for younger women of childbearing age.
The study followed 317 cases of glioma and compared them with 2,126 control subjects who did not have brain cancer. By focusing on women in their reproductive years, the researchers were able to directly assess how long-term exposure to hormones influenced cancer risk in this age group.
Use of hormonal contraceptives increased glioma risk significantly — Women who had ever used hormonal contraceptives showed a roughly 50% higher chance of developing glioma compared to those who never used them. For long-term users — defined as five years or more — the risk increased even further, reaching a nearly twofold difference.
Progestin-only methods drove the greatest risk — When researchers looked at the type of contraceptive, they found that progestin-only methods had the strongest association with glioma. For women who relied exclusively on progestin-only contraceptives, the risk more than doubled compared to non-users. This means that the specific hormone in use, not just contraceptives in general, played a role.
Women Left in the Dark While Risks Mount
ABC News highlighted how American women have used Depo-Provera without being told it's tied to brain tumor risks.6 Despite being approved by th
United States
