Nothing in this chapter shall be construed to apply to or interfere in any way with the practice of midwifery by a person who is enrolled in a program of midwifery approved and accredited by the secretary: PROVIDED, That the performance of such services is only pursuant to a regular course of instruction or assignment from the student's instructor, and that such services are performed only under the supervision and control of a person licensed in the state of Washington to perform services encompassed under this chapter.