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.

Mary Ruth Ziegler, a law professor at the University of California, Davis, School of Law, said a challenge to shield laws, which blue states started adopting in 2023, has been anticipated.

And it could have a chilling effect on prescriptions.

“Will doctors be more afraid to mail pills into Texas, even if they might be protected by shield laws because they don’t know if they’re protected by shield laws?” Ziegler said in an interview Friday.

The lawsuit accuses New York Dr. Maggie Carpenter of violating Texas law by providing the drugs to a Texas patient and seeks up to $250,000. No criminal charges are involved.

Texas bars abortion at all stages of pregnancy and has been one of the most aggressive states at pushing back against abortion rights. It began enforcing a state law in 2021 — even before the U.S. Supreme Court overturned Roe v. Wade and opened the door to state bans — that barred nearly all abortions by allowing citizens to sue anyone who provides an abortion or assists someone in obtaining one.

Paxton said that the 20-year-old woman who received the pills ended up in a hospital with complications. It was only after that, the state said in its filing, that the man described as “the biological father of the unborn child” learned of the pregnancy and the abortion.

“In Texas, we treasure the health and lives of mothers and babies, and this is why out-of-state doctors may not illegally and dangerously prescribe abortion-inducing drugs to Texas residents,” Paxton said in a statement.

The state said the Texas woman received a combination of two drugs that are generally used in medication abortions. Mifepristone blocks the hormone progesterone and primes the uterus to respond to the contraction-causing effect of the second drug, misoprostol. The two-drug regimen can be used to end pregnancies up through 10 weeks, but the drugs also have other uses and can help induce labor, manage miscarriages or treat hemorrhage.

The Abortion Coalition for Telemedicine, where Carpenter is co-medical director and founder, said in a statement that shield laws are essential to preserving abortion access.

“Ken Paxton is prioritizing his anti-abortion agenda over the health and well-being of women by attempting to shut down telemedicine abortion nationwide,” the group said. “By threatening access to safe and effective reproductive health care, he is putting women directly in harm’s way.”