Trial Date Set as Thousands Sue Pfizer Over Birth Control Linked to Brain Tumors

A class action lawsuit claiming that Depo-Provera, Pfizer’s popular birth control injection, caused brain tumors, is headed to trial.

A total of 2,132 women who developed brain tumors joined the class action lawsuit, which was filed in 2024. The women claim Pfizer knew that long-term use of Depo-Provera is linked to benign, though debilitating and potentially incurable brain tumors, but the drugmaker didn’t warn patients or regulators.

“Defendants willfully, wantonly, and intentionally conspired, and acted in concert, to ignore relevant safety concerns and to deliberately not study the long-term safety and efficacy of Depo-Provera, particularly in chronic long-term users of Depo-Provera,” the complaint states, according to an excerpt quoted by NBC News.

According to the Daily Mail, Depo-Provera “contains progestin, a synthetic version of the hormone progesterone, which prevents pregnancy by stopping ovulation and thinning the lining of the uterus.” The injection is administered every three months.

The U.S. Food and Drug Administration (FDA) licensed the drug in 1992.