Same playbook. Here we go again. Pfizer knew about issues with one of its blockbuster drugs, and did nothing. This time around, we’re talking about Depo-Provera, the contraceptive marketed to women as a major convenience. Don’t worry about taking a pesky pill every day. Instead, just take the Depo-Provera injection once every three months. Ah, the convenience of not having to take a pill every day.

Pfizer’s marketing campaign worked well. One in four American women have used Depo-Provera, known generically as medroxyprogesterone acetate. The medication is a hormonal contraceptive to prevent pregnancy. It contains no estrogen, and is a synthetic form of progesterone that prevents pregnancy by stopping ovulation, thickening the cervical mucus to make it more difficult for sperm to reach the egg, and thinning the uterine lining to reduce the likelihood of implantation.

But Depo-Provera has a problem. A big problem. It greatly increases the likelihood of women developing a certain kind of brain cancer. A new study shows the correlation. In a massive study of 61 million women, Depo-Provera increased the risk of a brain tumor called meningioma by a whopping 240%. In other words, for every 1,152 women given the Depo-Provera injections, one is expected to develop a meningioma directly attributable back to the injection. Women over age 31 who had used Depo-Provera for 4+ years were found to be at the highest risk.