Maine’s attorney general is joining his counterparts in other states in voicing support for a lawsuit challenging South Carolina’s new abortion law.

The attorneys general in 21 states argue in a brief filed in federal court Wednesday that the restrictive measure could harm their states by taxing resources if women cross borders to seek care.

“Reproductive health care is under attack across the country with numerous states – including South Carolina – taking steps to make abortion care nearly impossible to access safely,” Maine Attorney General Aaron Frey said in a statement Wednesday.

South Carolina’s law restricts abortion if a fetal heartbeat is detected. It’s one of more than a dozen similar measures passed across the country in recent years.

The law is on hold pending the outcome of a Mississippi abortion measure currently before the U.S. Supreme Court.