The 8th U.S. Circuit Court of Appeals is hearing oral arguments in the two cases Tuesday morning. The states are seeking to reinstate abortion restrictions approved by lawmakers in 2013 but overturned by lower federal courts in separate decisions.
The North Dakota law banned abortions when a fetal heartbeat can be detected, which can be as early as six weeks into pregnancy and before many women know they're pregnant. A U.S. District Court judge in Bismarck ruled the law unconstitutional in April 2014.
The Arkansas law banned abortions after 12 weeks. State lawmakers in the Republican-controlled Legislature overrode Democratic Gov. Mike Beebe's veto.