The Supreme Court on Wednesday will hear its first abortion case since President Trump’s two appointees took their seats, a dispute that could mark the first step in a gradual retreat from Roe vs. Wade.

Justices will weigh Louisiana’s claim — supported by the Trump administration — that doctors and clinics have no legal standing to challenge state regulations. Experts in abortion law say a high court ruling denying legal standing to doctors could have a far-reaching impact and make it far more difficult to challenge antiabortion measures in federal court.

Advocates on both sides of the abortion debate foresee a conservative majority giving states more freedom to restrict abortion without going so far as overturning the 1973 landmark ruling. Chief Justice John G. Roberts Jr., in particular, may prefer to avoid a major shift on abortion rights in an election year, experts say, though that decision could face the court in 2021 or after as it considers a wave of new state laws that would ban some or nearly all abortions.

The Louisiana case began in 2014 when lawmakers approved a measure, patterned on a Texas law, to require all doctors who perform abortions to have “active admitting privileges” at a nearby hospital. State officials defended this as a health and safety measure. They said it would help assure that only competent and trusted physicians were performing abortions and that their patients could be quickly transferred to a hospital in an emergency.

Abortion rights lawyers call the “admitting privileges” rule a deceptive scheme designed to shut down already embattled abortion clinics. They said that because early abortions are very safe, patients rarely are sent to a hospital. Typically, hospitals extend admitting privileges to doctors who regularly send patients. And because abortion remains controversial, many hospitals, especially in small towns and rural areas, are wary of having an affiliation with a doctor who performs abortions.

In Louisiana, the law could shut down all but one abortion provider.

The Supreme Court rejected an admitting privileges rule in Texas in 2016, when Justice Anthony M. Kennedy joined liberals to say — in Whole Woman’s Health vs. Hellerstedt — that the law put an “undue burden” on women. Lawyers for the Center for Reproductive Rights argued the Texas law left hundreds of thousands of women across vast stretches of south and west Texas with no doctors or clinics licensed to perform abortions. For them, the state’s rule was a danger to their health, not a benefit, they said.

Abortion rights advocates celebrated what they thought was a historic victory. But the court has changed significantly since then. In 2017, Trump named Justice Neil M. Gorsuch to replace the late Justice Antonin Scalia. And when Kennedy retired in 2018, Trump named Justice Brett M. Kavanaugh to replace him. For the first time, the court appears to have a majority of conservative justices inclined to sharply limit abortion rights or overturn Roe vs. Wade entirely.

It did not take long for a new challenge to arise. Just days before before Kavanaugh won confirmation in the Senate, the U.S. 5th Circuit Court of Appeals in New Orleans announced a surprise decision. A federal judge had blocked Louisiana’s admitting privileges law based on the high court’s ruling in the Texas case.

But by a 2-1 vote, the appeals court overturned that decision and upheld the law on the grounds that the situation in Louisiana was “remarkably different” from that in Texas. “Driving distances” are not as extreme as in the Lone Star state, the judges said. They also said several doctors in Louisiana may well be able to obtain admitting privileges if they kept trying.

Abortion rights lawyers filed an emergency appeal with the high court, seeking a temporary order to block the law from going into effect. They said the 5th Circuit Court had “brazenly ignored” the high court’s 2016 decision. And they said abortion facilities in Shreveport and Baton Rouge may be forced to close, leaving just one clinic in New Orleans.

In February 2019, the high court issued a one-line order that put the Louisiana law on hold until a full appeal could be considered. The vote was 5 to 4. Roberts, having dissented in the Texas case, joined with the four liberal justices, while four conservatives — Justices Clarence Thomas, Samuel A. Alito Jr., Gorsuch and Kavanaugh — dissented.

In October, the court agreed to hear arguments and decide the Louisiana case. Though it marks the first abortion case the court has agreed to hear since Gorsuch and Kavanaugh joined, justices have taken other actions on the issue. They have refused to hear several abortion appeals, including an Indiana law that would have barred women from ending a pregnancy after receiving a diagnosis of Down syndrome. In another case, justices in a brief order upheld a measure that required clinics to bury or cremate the remains of a fetus.

Granting the Louisiana case came with a surprise. While agreeing to review the 5th Circuit’s ruling, the justices also said they would decide a separate appeal from the Louisiana attorney general questioning whether the doctors and clinics had “third party standing” to challenge the state law.

Since the 1970s, nearly all the court’s abortion cases arose when doctors, clinics or a group like Planned Parenthood sued — not to defend their right to practice medicine but, rather, their patients’ right to obtain an abortion. Louisiana state lawyers, backed by the Trump administration, alleged a “serious conflict of interest” between what’s good for the doctors and what’s good for patients.

“The doctors perform very brief procedures on drugged patients whom they never saw before and will never see again,” the state’s lawyers said. Yet in court, they “challenge a Louisiana health statute designed to protect those very patients from unscrupulous and incompetent abortion providers.”

Legal experts were taken aback by the court’s willingness to consider the standing of doctors and clinics to bring lawsuits.

“Taking the standing question was a bombshell,” said Mary Ziegler, a Florida State University law professor. “This is a part of the reversal strategy on the antiabortion side. They want to argue that abortion is unsafe, that it hurts women and that abortion providers are in it for profit. And practically, it could make it much more complicated to bring lawsuits” to challenge abortion laws, she said.

Helen Alvare, a law professor at the Antonin Scalia Law School in Virginia and a critic of the Roe decision, said the court’s willingness to take up the standing question is “a really interesting development. Pro-lifers see this an opportunity to shape the public narrative. It raises the question of whether abortion providers are on the side of women.”

Abortion rights advocates say a victory for Louisiana in June Medical Services vs. Russo would send an ominous signal. “If the court allows the Louisiana law to stand, we will probably look back on this case as the acceleration of the total demise of the right to abortion in this country,” said Gretchen Borchelt, vice president for reproductive rights at the National Women’s Law Center. “Without overruling Roe, the court could gut what is left of the constitutional right to abortion.”