Have you looked into direct entry master's degree program? From what I understand, someone with a Bachelor's degree in something other than nursing can enter the program and sit for the NCLEX after a year or two and graduate with a Master's in midwifery as a CNM. Check out Ohio State (
http://www.con.ohio-state.edu/prospective_masters.htm ) ...they have such a program and I am sure there are more, just none coming to mind at the moment.
Also you can get a master's degree in Midwifery without being a nurse first. You are classifies as a CM (certified midwife) rather than a CNM, but this course of action is still in its pioneering stage and I think some state may not recognize this in the same light as a CNM. Check out the American college of Nurse Midwives for more info (
http://www.acnm.org/ )
HTH