Mich. Comp. Laws § 550.1401f

Sec. 401f. (1) A health care corporation certificate that requires a member to designate a participating primary care provider and provides for annual well-woman examinations and routine obstetrical and gynecologic services shall permit a female member to access an obstetrician-gynecologist for annual well-woman examinations and routine obstetrical and gynecologic services. (2) A health care corporation shall not require prior authorization or referral for access under subsection (1) to an obstetrician-gynecologist who participates with the health care corporation. A health care corporation may require prior authorization or referral for access to a nonparticipating obstetrician-gynecologist. (3) A description of the benefit provided by this section shall be included by the health care corporation in a communication sent to the individual or group purchaser of coverage.