Inside Mississippi’s only abortion clinic, administrator Shannon Brewer has been fielding phone calls from women who want to know whether they can still terminate a pregnancy if they think they might be more than a few weeks along.

The confusion comes from a Mississippi law that’s set to ban abortions after a fetus’s heartbeat is detected: about six weeks into a pregnancy, before many women know they are pregnant. The clinic has sued to block it, and a judge was scheduled to hear arguments on the request Tuesday.

Brewer says that since abortion has been in the news frequently for the past few months, the Mississippi clinic, the Jackson Women’s Health Organization, is receiving calls from potential patients not only from inside the state but also from Alabama, Florida, Georgia, Louisiana and Tennessee.

“They’re calling to make sure we’re not closed,” she said.

The Mississippi law, signed by Republican Gov. Phil Bryant in March, says physicians who perform abortions after a fetal heartbeat is detected could face revocation of their state medical licenses. It also says abortions could be allowed after a fetal heartbeat is found if a pregnancy endangers a woman’s life or one of her major bodily functions. Legislators rejected efforts to allow exceptions for pregnancies caused by rape or incest.

The Jackson Women’s Health Organization says the law is unconstitutional under the U.S. Supreme Court’s 1973 Roe v. Wade decision, which legalized abortion nationwide.

Abortion opponents have pushed new restrictions in several states this year — the most recent being Alabama, which just last week passed a law banning nearly all abortions — in the hopes that a case will make its way to the high court. They are emboldened by new conservative justices on the court appointed by President Donald Trump, who tweeted over the weekend that he opposes abortion except in cases of rape, incest or danger to the life of the pregnant woman.

U.S. District Judge Carlton Reeves is scheduled to hear arguments on Tuesday over the clinic’s request for him to stop the law from taking effect July 1. It was unclear whether Reeves would issue a decision immediately.

If Reeves were to temporarily block the law, he would hear arguments later on the larger question of constitutionality. In 2018, Mississippi enacted a law to ban abortions after 15 weeks, and Reeves struck it down, writing that it “unequivocally” violates women’s constitutional rights.

Governors in Georgia, Kentucky and Ohio have also signed bans on abortion once a fetal heartbeat is detected. Missouri lawmakers passed an eight-week ban Friday. Other states, including Louisiana, are considering similarly restrictive laws. None of the laws that have been signed have yet taken effect. All are expected to be blocked while challenges work their way through courts.

“Other states are following Mississippi with heartbeat bills,” Bryant tweeted on Sunday. “A new national movement has begun. We now have a President that stands for the unborn. Look for the left to increase their hateful attacks.”

Jackson Women’s Health Organization has four physicians who travel from Atlanta, Boston and California to do abortions, Brewer said.

Abortion opponents stand outside the bright pink clinic several days each month to sing, pray and beseech women not to go inside.

Posters inside the clinic tell about the most effective birth control methods, and a basket of condoms sits in the room where women are required under a years-old Mississippi law to receive counseling at least 24 hours before an abortion can be done. They have to make a second trip to the clinic to have the procedure.

Brewer said the earliest point at which the clinic does abortions is at about six weeks of pregnancy, and the average is at about eight to 10 weeks. The latest the clinic will do an abortion is 16 weeks.

Banning abortion after six weeks “is the same as banning abortion,” she said.

Republican state Sen. Angela Hill of Picayune was one of the main sponsors of the Mississippi bill. During a Senate debate in February, Hill fought back tears as she said she said it would help women and children.

“I see in this country that we protect sea turtle eggs and we protect other endangered species of animals with a greater degree of scrutiny and zealousness than we protect a child in the womb,” Hill said.