A 2024 British Medical Journal (BMJ) study linked use of injectable Depo-Provera to an increased risk of intracranial meningioma. The researchers looked at those who used medroxyprogesterone acetate injections (Depo-Provera shots) as their primary form of birth control. They concluded that people who used Depo-Provera for a year or more were five times more likely to develop meningioma requiring surgery.
Since an estimated 74 million women around the world use Depo-Provera for birth control, the researchers surmised that the number of meningiomas connected to the contraception could be high.
Researchers also looked at meningioma risk for other forms of birth control, including other hormonal treatments like progesterone, dydrogesterone and some hormonal intrauterine devices (IUDs). They found no increased risk for these types of birth control.
How likely is Depo-Provera to cause meningioma?
The BMJ study analyzed meningioma cases among people who had taken MPA (Depo-Provera) and those who had not. MPA users who used the medical drug for a year or more were at about 5.6 times greater risk of meningioma than non-users.
What is meningioma?
Meningiomas are a type of brain tumor that is usually non-malignant. These tumors originate in the tissue (meninges) covering the spinal cord and the brain. They are commonly found near the top and the outer curve of the brain, but may also form at the base of the skull. They can spread to other parts of the central nervous system through cerebrospinal fluid. Although typically characterized as slow-growing and benign tumors, some meningiomas grow rapidly and constrict nearby brain tissue. When this happens, surgery is required.
There are three grades of meningiomas:
- Grade 1: The most common meningiomas, which tend to grow slowly
- Grade 2: Mid-grade meningiomas, with a higher risk of coming back if removed
- Grade 3: Malignant, cancerous and fast-growing meningiomas
The symptoms of meningiomas often vary with where the tumor forms. Some potential symptoms include:
- Confusion
- Headaches (more severe in the morning)
- Inability to hear or smell
- Seizures
- Vision issues
People with malignant meningiomas commonly undergo surgery to remove the tumor, followed by radiation or chemotherapy. They sometimes participate in clinical trials to test the potential effectiveness of new treatments and medications.
How does Depo-Provera work?
Depo-Provera is an injectable form of birth control made by Pfizer. It works by blocking ovulation, or the release of an egg from a woman's ovary during the reproductive cycle. If a woman doesn’t ovulate, she can’t become pregnant. As an additional protection against ovulation, Depo-Provera thickens the cervical mucus to stop sperm from reaching the egg.
Women who use Depo-Provera receive a shot — commonly called the Depo shot or birth control shot — on a routine schedule every three months. A doctor injects the medication into the patient’s arm or buttocks. Depo-Provera contains a progesterone hormone that can protect against pregnancy for up to 14 weeks, although the shots are usually given every 12 weeks.
