Attorney Erin Hawley, representing the anti-abortion Alliance for Hippocratic Medicine that is challenging mifepristone, has begun her presentation to the justices.

Hawley is echoing the alliance's attacks on the drug's use and regulation by the FDA, contending that it creates harm to women and burdens doctors who must then care for such patients who use mifepristone.

Hawley also invoked an "intolerable" choice that is created by the widespread use of mifepristone -- if an anti-abortion doctor must consider treating abortion patients in an emergency situation or not.

-ABC News' Adam Carlson

Jessica Ellsworth, the attorney for Danco Labs, was asked by Justice Ketanji Brown Jackson if she was concerned about the prospect of judges parsing medical and scientific studies without specialized knowledge.

"I think we have significant concerns about that," Ellsworth said, noting the pharmaceutical industry submitted briefs to the court expressing that worry.

She went on to state that U.S. District Judge Matthew Kacsmaryk, who initially ruled to suspend mifepristone's approval, relied on studies that "were not in the administrative record" and never would have been.

"They have since been retracted for lack of scientific rigor and misleading presentations of data," she said.

Sage Publishing said it issued the retractions from the journal Health Services Research and Managerial Epidemiology because of methodology issues and conflicts of interest, ABC News previously reported.

Justice Samuel Alito asked Jessica Ellsworth, the attorney representing Danco Laboratories, if she thinks the FDA should have continued requiring prescribers to report non-fatal complications, known as “adverse events" of mifepristone.

Ellsworth argued the FDA made that decision after 15 years of data that established mifepristone was safe. She also rejected Alito's question asking if the FDA was "infallible".

Justice Kentanji Brown Jackson asked if the defendants had concerns about judges "parsing medical and scientific studies" and Ellsworth said there were concerns.

Jessica Ellsworth, who is representing the manufacturer of Mifeprex (the brand name of mifepristone), similarly criticized the plaintiff's claim of injury and their interpretation of the law.

She said the respondent's view is "so inflexible it would upend not only Mifeprex but virtually every drug approval and [risk and mitigation] modification the FDA has made for decades."

Medication abortion quickly became the target of multiple lawsuits after the Supreme Court struck down Roe's guarantees to national abortion access.

Last year, U.S. District Judge Matthew Kacsmaryk in Texas issued an unprecedented ruling suspending the FDA's initial approval of the drug (which has been on the market for nearly 25 years) because, he said, the drug was unsafe and its approval process rushed.

Kacsmaryk's order was partially blocked by the 5th U.S. Circuit Court of Appeals, though that court held the FDA acted unlawfully when it eased rules in 2016 and 2021 to allow the pill to be mailed to patients, prescribed by a medical professional and taken later in pregnancy.

The Biden administration then appealed to the U.S. Supreme Court, warning the loss of access would be "damaging for women and healthcare providers" nationwide and defending the FDA's process as supported by science and decades of safe use.