Does it matter who petitions primary custody first in iowa court?

It does not.  The only benefit of filing first is that you get to go first at presenting evidence if you have to go to court.  The first filer does not have an easier time getting custody - they still have to convince the judge as to the best interests of the children.  The filer also has to pay the filing fee, though there is usually an order at the end for the parties to split that.   Donna Miller 515-245-43030 http://www.grefesidney.com/our-team/donna-miller/