Complex sentence: There are currently more M.D. schools than D.O. schools offering medical training in the United States, however, the D.O. medical profession is expanding rapidly, with approximately 1 in 4 medical students now entering a D.O. medical school.
Split into simpler sentences: There are currently more M.D. schools than D.O. schools offering medical training in the United States. However, the D.O. medical profession is expanding rapidly, with approximately 1 in 4 medical students now entering a D.O. medical school.