ATLANTA — A federal judge blocked Georgia’s anti-abortion law from going into effect Jan. 1.

District Judge Steve C. Jones ruled Tuesday that the law should not be enacted while it is under challenge in federal court.

The American Civil Liberties Union, along with a large pool of women’s rights organizations, sued the state, saying the law is unconstitutional. If it goes into effect, an abortion would be prohibited as soon as a doctor can detect a fetal heartbeat.