My wife is 39 weeks pregnant and only .5cm dilated. does this mean she is going to deliver past her due date or go into labor soon? thanks

Either possible: A due date is only an approximation of when the baby will come. It is perfectly normal to deliver from 37-42 weeks pregnant as long as everything is properly supervised and going well. If this is her first pregnancy, they tend to go a little later and frequently do not dilate until actual labor occurs. Congrats on your upcoming baby.