In a letter to Head of Instagram Adam Mosseri and Meta CEO Mark Zuckerberg, Senators Amy Klobuchar and Elizabeth Warren expressed alarm that abortion-related content is receiving strange treatment on Meta’s platforms.

Just after the Supreme Court ruled to overturn Roe v. Wade, Motherboard found that posts offering to provide abortion pills were being removed from Facebook within seconds of being posted. The Associated Press observed similar posts about abortion pills vanishing from Instagram “within moments.” Instagram also hid some abortion-related content behind warning screens, behavior that the company described as a “bug” but didn’t explain further.

The senators went into some detail about the abortion-related posts and accounts Meta removed:

“Reports indicate that multiple posts providing accurate information about how to legally access abortion services were removed, often within minutes after the information was posted. Others reported that posts mentioning abortion were taken down or were tagged with “sensitivity screens” and warnings, including a post promoting an abortion documentary, a posting entitled “Abortion in America How You Can Help,” and a post from a healthcare worker describing how people were already being harmed by laws banning abortion. One organization dedicated to informing people in the United States about their abortion rights temporarily had its account suspended. Users reported similar issues last fall when Texas’s law banning abortions after six weeks went into effect.”

In a Twitter reply, Meta Policy Communications Director Andy Stone noted that the company’s policies do not allow transactions of prescription drugs, but did not explain the enforcement discrepancy between the abortion pill posts and posts offering to provide other prescription drugs.

Klobuchar and Warren are requesting “additional information about what Meta is doing to address problems applying company policies” — information that could explain Meta’s conspicuously aggressive handling of the abortion-related content.

The senators are asking Meta for answers to a number of questions that the company hasn’t been transparent about on the topic, including how many abortion-related posts it has removed since June 24, how many of those posts have been reinstated and what training materials about abortion the company provides to its content moderators. The requests have a deadline of July 15.