We were told by midwifery programme leader at presentation they have around 1000 applicants for 90 spaces. Obviously it will vary with uni but gives you a rough idea.
In regards to interview, I doubt there is any information on that as it will depend on the individual. However again we were told that if they want you they will give you an offer regardless of space - they will just offer you a later start date if places filled up ie the next year.