Advocates are preparing for a legal battle after Alabama passed the strictest abortion bill in the country late Tuesday, part of a growing national push by abortion opponents to test whether the courts will curb constitutional protections for the procedure.

Alabama’s move, which would essentially ban abortion in most cases, could open the door to restrictions in other states — even though they will all likely be challenged in court. Other states are already pursuing and defending laws to ban abortion after six weeks of pregnancy.

[Trump civil rights official wants to defend abortion opponents and religious freedom]

“This is not just about Alabama. We are seeing these extreme bills being introduced across the country,” said Planned Parenthood President Leana Wen in a call with reporters Wednesday. “These extreme bans banning abortions at six weeks or earlier, before women even know we’re pregnant, is happening in 16 states.”

Alabama’s bill, which Wen called the most extreme abortion ban since the landmark Roe v. Wade case guaranteed a national right to abortion in 1973, would go farther than the approach taken in many other red states. The legislation would ban abortion at any stage of pregnancy, unless needed to save the life of the woman, and has no exceptions for rape or incest. Abortion providers who violate these terms could be charged with a felony and punished for up to 99 years in prison.