Texas has sued a New York doctor for prescribing abortion pills to a woman near Dallas, launching one of the first challenges in the U.S. to shield laws that Democrat-controlled states passed to protect physicians after Roe v. Wade was overturned.

Texas Attorney General Ken Paxton filed the lawsuit on Thursday in Collin County, and it was announced Friday.

Such prescriptions, made online and over the phone, are a key reason that the number of abortions has increased across the U.S. even since state bans started taking effect. Most abortions in the U.S. involve pills rather than procedures.