A federal judge has ruled a new state law that would ban abortion after a fetal diagnosis of Down syndrome is unconstitutional, and has blocked it a little more than a week before it was to go into effect.

Ohio would have been the third state with a Down syndrome abortion ban, after Republican Gov. John Kasich signed the measure into law in December. But U.S. District Court Judge Timothy Black writes that federal law is crystal clear that a state may not prohibit a woman from deciding to terminate a pregnancy before viability. He says opponents are "highly likely" to successfully argue the law is unconstitutional.

The ACLU filed the suit last month against the state Department of Health, state medical board and county prosecutors on behalf of Planned Parenthood and several abortion providers. It's seeking to have the law declared unconstitutional and thrown out.

In a statement, pro-choice groups said they’re committed to stopping the law, which they say would interfere with the trust between women and doctors and open the door to further intrusion by politicians into personal health decisions. The law won't take effect while the ACLU's lawsuit proceeds.

Ohio Attorney General Mike DeWine, himself pro-life, is reviewing the decision but will fiercely defend the law.

Ohio Right to Life said in a statement that the court prioritized “abortion-on-demand” over special needs children, but that it’s pleased DeWine will defend the law.