Jackson County Circuit Judge Jerri Zhang was set to hear arguments from Planned Parenthood and the state’s Republican Attorney General’s Office over whether to issue a temporary order blocking enforcement of Missouri’s numerous abortion laws.

“If left in place, the above-described restrictions will continue to be catastrophic for Missourians,” lawyers for abortion-rights supporters wrote in a court brief. “They will either prevent care altogether or severely delay or interfere with care.”

Missouri is one of five states where voters approved ballot measures this year to add the right to an abortion to their state constitutions. Nevada voters also approved an amendment, but they’ll need to pass it again in 2026 for it to take effect. Another that bans discrimination on the basis of “pregnancy outcomes” prevailed in New York.

Reproductive rights advocates in Arizona on Tuesday sued to undo a 15-week abortion ban that conflicts with that state’s new constitutional amendment expanding access up to fetal viability.

The Missouri amendment does not specifically override any state laws. Instead the measure leaves it to advocates to ask courts to knock down bans that they believe would now be unconstitutional.

Missouri Attorney General Andrew Bailey, an abortion opponent, last week issued an opinion agreeing that most abortions will be legal when the amendment takes effect Thursday.

But Bailey’s office is still fighting for a ban on most abortions after viability, along with a number of regulations that Planned Parenthood argues made it nearly impossible to offer abortions in the state even before abortion was almost completely banned in 2022.

Missouri’s constitutional amendment allows lawmakers to restrict abortion after viability, with exceptions to “protect the life or physical or mental health of the pregnant person.”

The term “viability” is used by health care providers to describe whether a pregnancy is expected to continue developing normally or whether a fetus might survive outside the uterus. Though there’s no defined time frame, doctors say it is sometime after the 21st week of pregnancy.

Other abortion laws that Bailey is defending include a 72-hour waiting period before an abortion can be performed; bans on abortions based on race, sex or a possible Down syndrome diagnosis; and a requirement that medical facilities that provide abortions be licensed as ambulatory surgical centers.

The Attorney General’s Office argued that Planned Parenthood has not proven it will be negatively impacted by those laws, noting that no abortions have been scheduled yet.

“Planned Parenthood concedes they have no appointments scheduled for right after the amendment goes into effect and have not even tried to obtain relevant licenses or create necessary complication plans,” state attorneys wrote in a court brief.

It is unclear when Zhang will rule on the request for a preliminary injunction.