AUSTIN, Texas — A federal appeals court on Tuesday upheld Texas’ strict abortion restrictions that could soon leave only seven abortion clinics open in a state of 27 million people.

The decision by the 5th U.S. Circuit Court of Appeals allows Texas to enforce Republican-backed restrictions that require abortion clinics to meet hospital-level operating standards, a checklist that includes rules on minimum room sizes, staffing levels and air ventilation systems. The restrictions, approved in 2013, are among the toughest in the nation.

Owners of traditional abortion clinics, which resemble doctor’s offices more than hospitals, say they would be forced to close because the rules demand millions of dollars in upgrades they can’t afford. That would mark the second large wave of closures in as many years in Texas, which had 41 abortion clinics in 2012, before other new restrictions took effect that require doctor admitting privileges.

“Not since before Roe v. Wade has a law or court decision had the potential to devastate access to reproductive health care on such a sweeping scale,” said Nancy Northrop, president and CEO of the Center for Reproductive Rights. “We now look to the justices to stop the sham laws that are shutting clinics down and placing countless women at risk of serious harm.”

Texas will be able to start enforcing the restrictions in about three weeks unless the U.S. Supreme Court agrees to halt the decision, said Stephanie Toti, an attorney for the center. Only seven abortion facilities in Texas, including four operated by Planned Parenthood, meet the more robust requirements.

Abortion-rights groups said they will appeal to the U.S. Supreme Court, which temporarily sidelined the law last year.

If the law takes effect, some women in the state would live hundreds of miles away from a Texas abortion provider. But that argument didn’t sway the three-judge panel making the decision for the New Orleans-based appeals court, which is considered one of the most conservative in the nation.

The judges noted that a New Mexico abortion clinic was just across the Texas border, and said clinic owners in Texas failed to prove that a “large fraction” of women would be burdened.