Women who use Depo-Provera face a higher risk of developing a slow-growing brain tumor, according to a new study that comes as the contraceptive’s maker, Pfizer, faces hundreds of lawsuits claiming that it was aware of the potential risks.
Depo-Provera — the brand name for depot medroxyprogesterone acetate (DMPA) — contains the synthetic progestin hormone, which stops the ovaries from releasing an egg to prevent pregnancy.
The injections, used by roughly 1 in 4 sexually active US women at some point, last about three months.
For the new study, researchers examined over 61 million female patient records, finding that women who used DMPA had a twofold higher risk of getting diagnosed with meningioma compared to women not on hormonal birth control.
Meningioma is typically benign, but the tumors can cause problems by putting pressure on nerves or brain structures. The disease affects women more frequently than men, likely due to the influence of female hormones that can fuel tumor growth.
The researchers, from the Cleveland Clinic and Case Western Reserve University, found the greatest meningioma risk in women who started DMPA after the age of 31 or those who used it for four-plus years.
“In this study, women receiving [DMPA] had a greater relative risk of subsequent meningioma diagnosis, especially with prolonged exposures and starting the medication at older ages,” the study authors wrote in JAMA Neurology.
The research was observational, meaning it didn’t provide proof that DMPA causes meningioma.
Medroxyprogesterone acetate was initially synthesized in 1954 to treat endometriosis, uterine fibroids and other gynecological conditions.
The US Food and Drug Administration (FDA) rejected Depo-Provera for contraceptive use for many years due to worries about cancer risks before finally approving it in 1992, following additional studies and after it had been used as a contraceptive in other countries.
The concerns didn’t stop there. A “black box” warning was added in 2004 to its label, alerting users that it could lead to significant bone mineral density loss, particularly with long-term use.
Then last year, a French study published in The BMJ found that women who used Depo-Provera for over a year had a 5.6 times greater risk of developing a meningioma.
Now, Pfizer is facing over 1,200 federal lawsuits related to Depo-Provera, with women alleging that the pharmaceutical giant failed to warn them about the meningioma risk.
One Louisiana plaintiff, Robin Phillip, said she developed an intracranial meningioma that caused her to lose vision in her left eye and struggle to walk.
“These women all have meningiomas. Many have surgery, some have radiation, and they’ve all had their lives greatly impacted,” Ellen Relkin, a lawyer representing Phillip and other plaintiffs, told NBC News.
Phillip’s lawsuit claims that there are studies dating back to 1983 linking progesterone and meningioma, NBC News reported, so Pfizer should have studied Depo-Provera risks sooner.
A Pfizer rep told The Post that “these claims are without merit and will vigorously defend against these allegations.”
Pfizer filed a motion in August to dismiss litigation, citing its 2023 discovery of a potential link between Depo-Provera and meningioma, NBC News reported.
The company said it had asked the FDA to update the label with a warning, but the agency denied the request because the available studies didn’t support the warning.
Pfizer told The Post that it “stands behind the safety and efficacy of Depo-Provera, which has been used by millions of women worldwide and remains an important treatment option for women seeking to manage their reproductive health.”
