A federal court in San Francisco Tuesday struck down Arizona's ban on abortions after 20 weeks of pregnancy unless there's a medical emergency.

The 9th U.S. Circuit Court of Appeals ruled that the law violates a string of U.S. Supreme Court rulings starting with Roe v. Wade, guaranteeing a woman's right to an abortion before a fetus is able to survive outside the womb. That's generally considered to be about 24 weeks. Normal pregnancies run about 40 weeks.

“We’re glad the court has reaffirmed that states cannot place unlawful burdens on a woman’s right to access safe reproductive health care," said Talcott Camp, deputy director of the ACLU Reproductive Freedom Project.

"Politicians do not have the right to interfere in serious and personal decisions that should only be made by a woman with the help of her family and her doctor," Camp said in a press release from the ACLU of Arizona.

Several states have enacted similar bans starting at 20 weeks. But the 9th Circuit's ruling is binding only in the nine Western states under the court's jurisdiction. Idaho is the only other Western state covered by the 9th Circuit with a similar ban.