A new medical study has linked the injectable contraceptive Depo-Provera to an increased risk of brain tumors, as more than 1,000 women have filed lawsuits against its manufacturer, Pfizer Inc., claiming they were not adequately warned about the potential dangers.
The study, which reviewed medical data from millions of women, found that those who used Depo-Provera for more than four years—or began using it after the age of 31 had about double the risk of developing meningioma, a type of brain tumor that forms in the membranes surrounding the brain and spinal cord. The research also indicated that even a year of use was linked to a 5.6-fold higher risk of developing the tumor compared to women who never used the injection.
According to The Guardian, Reuters, and The New York Post, the lawsuits are part of a growing multidistrict litigation (MDL) in Florida, where women allege that Pfizer failed to properly warn users and healthcare providers about the tumor risk associated with Depo-Provera. The plaintiffs say they experienced serious medical complications some requiring brain surgeries, radiation, or long-term treatment after using the contraceptive.
Meningiomas are typically non-cancerous but can cause severe health problems depending on their size and location. Symptoms may include headaches, vision loss, hearing problems, and seizures. Some women involved in the lawsuit say the drug left them with permanent neurological damage.
Pfizer, in its response, has denied wrongdoing and insists the product is safe. “Pfizer stands behind the safety and efficacy of Depo-Provera and will vigorously defend against these claims,” the company said in a statement reported by The New York Post. The pharmaceutical giant also stated that the U.S. Food and Drug Administration (FDA) had previously rejected label updates regarding tumor risks, arguing that federal regulations limit the company’s ability to change warnings without prior approval.
Experts caution that while the study findings show a strong association between Depo-Provera and meningioma, they do not conclusively prove that the contraceptive directly causes brain tumors. Dr. James Howard, a neurology researcher cited by Nation of Change, said the data “raises valid concerns but does not establish causation.” Still, he urged long-term users to “speak with their doctors about continued use and possible screening.”
Depo-Provera, a progestin-only contraceptive injection, has been widely used since the 1990s and is often favored for its convenience, providing three months of pregnancy prevention per dose. It remains approved for use in many countries, though regulators in France and Belgium have issued restrictions or warnings following similar studies.
Legal experts say the outcome of the U.S. lawsuits could influence future regulations and product labeling for hormonal contraceptives. Plaintiffs’ attorneys expect the number of cases to grow as more women come forward. “These women deserve transparency and accountability,” said one lawyer involved in the litigation.
For now, health professionals advise women who have used Depo-Provera long-term or who began using it later in life to consult their doctors. Until further investigations are complete, both the scientific community and affected patients are watching closely as the court proceedings unfold.
